Hearing, mobility, and pain predict mortality: a longitudinal population-based study

Abstract

Objective

Measures of health-related quality of life (HRQL), including the Health Utilities Index Mark 3 (HUI3) are predictive of mortality. HUI3 includes eight attributes, vision, hearing, speech, ambulation, dexterity, cognition, emotion, and pain and discomfort, with five or six levels per attribute that vary from no to severe disability. This study examined associations between individual HUI3 attributes and mortality.

Study Design and Setting

Baseline data and 12 years of follow-up data from a closed longitudinal cohort study, the 1994/95 Canadian National Population Health Survey, consisting of 12,375 women and men aged 18 and older. A priori hypotheses were that ambulation, cognition, emotion, and pain would predict mortality. Cox proportional hazards regression models were applied controlling for standard determinants of health and risk factors.

Results

Single-attribute utility scores for ambulation (hazard ratio [HR] = 0.10; 0.04–0.22), hearing (HR = 0.18; 0.06–0.57), and pain (HR = 0.53; 0.29–0.96) were statistically significantly associated with an increased risk of mortality; ambulation and hearing were predictive for the 60+ cohort.

Conclusion

Few studies have identified hearing or pain as risk factors for mortality. This study is innovative because it identifies specific components of HRQL that predict mortality. Further research is needed to understand better the mechanisms through which deficits in hearing and pain affect mortality risks.

1. Introduction

In population health studies, there is substantial evidence that baseline indicators of overall health-related quality of life (HRQL), such as self-rated health (excellent, very good, good, fair, or poor) predict subsequent health events including death [1–9]. For example, using data from the Manitoba Longitudinal Study on Aging, Mossey and Shapiro [1] found that after controlling for objective health status, age, sex, life satisfaction, and income, those who reported their health to be poor were nearly three times as likely to die as those who reported their health to be excellent. Gold et al. [10] using data from the National Health and Nutrition Survey I Epidemiologic Follow-up Study showed that the overall score on an HRQL measure, the Health Utilities Index Mark 1 based on four attributes (physical function, role function, social-emotional function, and health problem), predicted subsequent mortality after controlling for other determinants of health, including chronic conditions, smoking, income, age, gender, and education. Similarly, Wilkins [11] and Kaplan et al. [12] provided evidence of the relationship between baseline overall Health Utilities Index Mark 3 (HUI3) scores and subsequent mortality. HUI3 includes eight attributes of health status: vision, hearing, speech, ambulation, dexterity, emotion, cognition, and pain and discomfort.

Given that baseline overall HUI3 scores predict mortality, which of the individual HUI3 attributes might account for that prediction? Or is it a combination of deficits in multiple attributes that is important? The primary purpose of this study was to examine the association between individual HUI3 attributes and mortality risk prospectively and with a nationally representative population-based sample after adjusting for key covariates.

2. Methods

2.1. Health Utilities Index Mark 3

HUI3 is a generic preference-based measure of health status and HRQL. There are five or six levels per HUI3 attribute [13–15]. Levels within each attribute range from no disability (e.g., able to hear what is said in a group conversation with at least three other people, without a hearing aid) to severe disability (e.g., unable to hear at all). The health state of a subject at a point in time is summarized by the combination of the levels for each of the eight attributes (Table 1). There is substantial evidence on the construct validity of HUI3 in population health surveys [16–23].

Table 1.

HUI3: health-status classification system

Attribute	Level	Description
Vision	1	Able to see well enough to read ordinary newsprint and recognize a friend on the other side of the street, without glasses or contact lenses.
	2	Able to see well enough to read ordinary newsprint and recognize a friend on the other side of the street but with glasses.
	3	Able to read ordinary newsprint with or without glasses but unable to recognize a friend on the other side of the street, even with glasses.
	4	Able to recognize a friend on the other side of the street with or without glasses but unable to read ordinary newsprint, even with glasses.
	5	Unable to read ordinary newsprint and unable to recognize a friend on the other side of the street, even with glasses.
	6	Unable to see at all.
Hearing	1	Able to hear what is said in a group conversation with at least three other people, without a hearing aid.
	2	Able to hear what is said in a conversation with one other person in a quiet room without a hearing aid but requires a hearing aid to hear what is said in a group conversation with at least three other people.
	3	Able to hear what is said in a conversation with one other person in a quiet room with a hearing aid and able to hear what is said in a group conversation with at least three other people, with a hearing aid.
	4	Able to hear what is said in a conversation with one other person in a quiet room, without a hearing aid but unable to hear what is said in a group conversation with at least three other people even with a hearing aid.
	5	Able to hear what is said in a conversation with one other person in a quiet room with a hearing aid but unable to hear what is said in a group conversation with at least three other people even with a hearing aid.
	6	Unable to hear at all.
Speech	1	Able to be understood completely when speaking with strangers or friends.
	2	Able to be understood partially when speaking with strangers but able to be understood completely when speaking with people who know me well.
	3	Able to be understood partially when speaking with strangers or people who know me well.
	4	Unable to be understood when speaking with strangers but able to be understood partially by people who know me well.
	5	Unable to be understood when speaking to other people (or unable to speak at all).
Ambulation	1	Able to walk around the neighborhood without difficulty and without walking equipment.
	2	Able to walk around the neighborhood with difficulty but does not require walking equipment or the help of another person.
	3	Able to walk around the neighborhood with walking equipment but without the help of another person.
	4	Able to walk only short distances with walking equipment and requires a wheelchair to get around the neighborhood.
	5	Unable to walk alone, even with walking equipment. Able to walk short distances with the help of another person and requires a wheelchair to get around the neighborhood.
	6	Cannot walk at all.
Dexterity	1	Full use of 2 hands and 10 fingers.
	2	Limitations in the use of hands or fingers but does not require special tools or help of another person.
	3	Limitations in the use of hands or fingers and is independent with use of special tools (does not require the help of another person).
	4	Limitations in the use of hands or fingers and requires the help of another person for some tasks (not independent even with use of special tools).
	5	Limitations in use of hands or fingers and requires the help of another person for most tasks (not independent even with use of special tools).
	6	Limitations in use of hands or fingers and requires the help of another person for all tasks (not independent even with use of special tools).
Emotion	1	Happy and interested in life.
	2	Somewhat happy.
	3	Somewhat unhappy.
	4	Very unhappy.
	5	So unhappy that life is not worthwhile.
Cognition	1	Able to remember most things, think clearly, and solve day-to-day problems.
	2	Able to remember most things but have a little difficulty when trying to think and solve day-to-day problems.
	3	Somewhat forgetful but able to think clearly and solve day-to-day problems.
	4	Somewhat forgetful and have a little difficulty when trying to think or solve day-to-day problems.
	5	Very forgetful and have great difficulty when trying to think or solve day-to-day problems.
	6	Unable to remember anything at all and unable to think or solve day-to-day problems.
Pain	1	Free of pain and discomfort.
	2	Mild-to-moderate pain that prevents no activities.
	3	Moderate pain that prevents a few activities.
	4	Moderate-to-severe pain that prevents some activities.
	5	Severe pain that prevents most activities.

Abbreviation: HUI3, Health Utilities Index Mark 3.

Source ref. [14], p. 124.

HUI3 provides both single-attribute and overall utility scores. Single-attribute utility scores for HUI3 are on a scale in which the most severe level of disability for that attribute has a score of 0.00 and no disability/normal has a score of 1.00 [14]. For instance, the single-attribute utility scores for hearing are level 1 = 1.00, level 2 = 0.86, level 3 = 0.71, level 4 = 0.48, level 5 = 0.32, and level 6 = 0.00. Overall HUI3 scores are on the conventional scale in which dead = 0.00 and perfect health = 1.00.

The HUI3 scoring function is based on community preferences obtained from a random sample of the Canadian population elicited using a visual analog scale (VAS) and the standard gamble (SG). All health states were assessed on the VAS; a subset of health states was assessed on the SG. A power function was estimated to convert VAS into SG scores. The validity of the scoring function was confirmed by an examination of agreement between SG scores for 73 HUI3 health states obtained from a different random sample and scores derived from the HUI3 scoring function with an intraclass correlation coefficient of 0.88 [14].

2.2. Data

Data from the longitudinal Statistics Canada National Population Health Survey (NPHS) for 1994/95 through 2006/07 were used for the analyses. The NPHS is a closed cohort survey. The target population of the longitudinal NPHS component includes household residents in the 10 Canadian provinces in 1994/95 excluding persons living on Indian Reserves and Crown Lands, residents of health institutions, Canadian Forces bases, and some remote areas in Ontario and Quebec. Using a stratified, multistage random sampling procedure, 17,276 household members were selected to be interviewed every 2 years starting in 1994/95 to gather detailed health status, health service utilization, and sociodemographic data for the longitudinal component of the survey; see Tambay and Catlin [24] for a more complete description of the NPHS. Mortality was ascertained by proxy responses. Deaths up to December 31, 2005 were confirmed against the Canadian Vital Statistics Database [25]. In 13 cases, data on the date of death was missing. If the month of death was known, the date was imputed as the 15th; when the day and month were missing the day of death was imputed as 15 and month of death was imputed as June.

2.3. Independent variables

Single-attribute utility scores for each of the eight attributes are the key independent variables. The association among the 28 pairs of single-attribute scores was assessed.

2.4. Controlling for potential confounders

Standard risk factors and determinants of health identified by previous studies [12,26,27], all measured at baseline, were included in the analyses. These included sociodemographic factors (age, sex, marital status, household income, and education); number of chronic conditions associated with an elevated risk of mortality (high blood pressure, chronic bronchitis or emphysema, diabetes, heart disease, cancer; and stroke); possibly associated with an elevated risk of mortality (asthma and Alzheimer Disease or other dementia); and not associated with an elevated risk of morality (food allergies, allergies other than food allergies, arthritis or rheumatism, back problems excluding arthritis, migraine headaches, sinusitis, epilepsy, stomach or intestinal ulcers, urinary incontinence, cataracts, glaucoma, and other long-term conditions); body mass index; health behaviors (smoking, physical activity, and alcohol use); psychological health and resources (psychological distress, sense of coherence, and chronic stress); and perceived social support. The number of other attributes affected with any disability was included to assess the relative roles of specific deficits vs. combinations of deficits. Many chronic conditions often affect multiple attributes. For instance, type-2 diabetes might affect vision, ambulation, dexterity, cognition, emotion, and pain and discomfort.

Records with missing values for any of the covariates, except for income, were excluded from the analysis. Missing income was represented with an additional dummy variable. Some 1,742 records were excluded. Those excluded from the analyses were more likely to be younger, male, to have a lower level of education, and to be an immigrant.

2.4.1. A priori hypotheses

A priori predictions about the attributes expected to be associated with mortality were specified. Given the substantial evidence that deficits in physical health are predictive of mortality [28], lower scores on ambulation were expected to be associated with an increased risk of mortality. In addition, lower emotion, cognition [29], and pain scores were expected to be associated with an increased risk of mortality. Deficits in emotional health, cognition, and burdens because of pain are often associated with serious health problems, such as stroke, cardiovascular disease, and diabetes [21,30,31]. Further, there is substantial variation among individuals in the burdens associated with these four attributes.

2.5. Statistical analysis

The Cox proportional hazards model was used to assess mortality associated with each of the eight attributes, controlling for an array of potential confounders. Single-attribute HUI3 utility scores for each attribute were entered as continuous variables. Data were censored on the date of the last completed interview. All analyses were conducted using SAS, Version 9.1 (SAS Institute Inc., Cary, NC, USA). The bootstrap resampling technique was used [32] to account for the complex sampling design and to estimate hazard ratios (HRs), confidence intervals, and levels of significance. Weights used in adjustment for the sampling design were computed by taking into account poststratification and nonresponse in 1994/95. In addition, Yeo et al. [32] explain that the bootstrap weights were calculated in such a way as to generate accurate variance estimates while precluding data users from being able to identify respondents.

Cox models were estimated for two cohorts: those 18 years of age or older at baseline and those 60 years of age or older at baseline. The latter reflects the fact that deaths are concentrated at older ages.

Simulations were performed to illustrate the mortality impact of individual attributes, the HRs associated with each level within that attribute. By definition in the Cox model, the HRs were independent of variables other than the attribute being examined. Treating the single-attribute utility scores for the relevant attributes as continuous variables, the HRs for each level for each of the attributes that was a statistically significant predictor of mortality were then calculated for the 18+ and the 60+ cohorts. The unit of change in the simulations is a movement of one level within that attribute. Typically a change in level corresponds to a change of 0.05 or more (often substantially more) in the single-attribute utility score.

The study was approved by the Institutional Review Board of Portland State University.

3. Results

The main analysis is based on a total of 12,375 respondents who were 18 years of age or older at baseline. There were 1,701 deaths observed among 121,166 person-years of follow-up. Nearly 13% of the 14,177 respondents aged 18 and older who were interviewed at baseline were excluded from the analysis because of missing data on one or more covariates. Table 2 describes the sociodemographic characteristics and independent variables at baseline. Six percent of decedents were ages 18–49 at the time of their death, 8% were 50–59, 15% were 60–69, and 72% were 70+. Characteristics of those 60 years of age or older at baseline also are displayed.

Table 2.

Demographic characteristics of the baseline 1994/95 sample (n = 12,375 for 18+, m = 3,575 for 60+)

	For 18+		For 60 +
Demographic characteristics	Na	%b	Na	%b
Age
18–29	2,594	22
30–39	2,854	25
40–49	2,194	20
50–59	1,631	14
60–69	1,452	11	1,655	51
70–79	1,163	7	1,340	36
80+	487	2	580	13
Sex
Male	5,518	48	1,446	44
Female	6,857	52	2,129	56
Marital status
Single	2,737	21	263	6
Married	7,063	65	1,816	63
Widowed	1,239	6	1,218	25
Separated/divorced	1,336	8	278	6
Immigrant status
Nonimmigrants	10,663	81	2,906	75
Immigrants	1,712	19	664	25
Income
Lowest	2,760	17	1,100	23
Lower middle	3,661	29	1,353	38
Upper middle	4,092	35	755	26
Highest	1,420	15	175	7
Missing	442	4	192	6
Education
Less than high school	3,582	25	1,928	50
High school graduation	1,903	16	419	13
Completed or currently enrolled in college/university	6,890	58	1,215	36
Residential environment
Urban	9,342	83	2,602	82
Rural	3,033	17	973	18
SRH
Excellent	2,828	26	440	14
Very good	4,628	37	1,014	28
Good	3,333	27	1,133	34
Fair	1,236	8	695	19
Poor	350	2	215	6

Abbreviation: SRH, self-rated health.

^an is the unweighted sample size.

^bPercentage (%) is the weighted proportion.

The distribution of HUI3 levels within each attribute at baseline for the 18+ and 60+ cohorts is listed in Table 3. Very few subjects reported levels 5 and 6 (severe disability [33,34]) for most attributes. For 18+, the prevalence of severe disability at baseline exceeded 1% only for cognition and pain; for 60+, the prevalence of severe disability varied from 1.2% to 6.1%. Two percent of subjects 18–39 years of age at baseline had any impairment in hearing (levels 2–6), 3% had any hearing impairment in the 40–54 age range, 8% in the 44–59 age range, and 21% in the 70+ group.

Table 3.

Frequency distribution (%) of HUI3 attribute levels for all respondents, n = 12,375 for 18+; n = 3,575 for 60+ in parentheses

Levels	Vision	Hearing	Speech	Ambulation	Dexterity	Emotion	Cognition	Pain
1	45.7 (14.1)	95.3 (85.6)	99.1 (98.2)	96.7 (88.7)	98.9 (97.8)	74.6 (74.7)	69.2 (63.7)	82.2 (71.5)
2	51.7 (79.5)	2.3 (6.1)	0.7 (1.1)a	0.8 (1.9)	0.7b (1.3)a	22.4 (21.3)	17.0 (21.4)	5.5 (6.5)
3	0.7 (1.7)	0.5 (2.6)	0.3b	1.7 (5.9)		2.2 (3.01)a	5.5 (4.0)	5.9 (10.1)
4	1.3 (2.7)	1.5 (3.7)		0.6b (2.6)a	0.4b	0.5	6.4 (7.9)	3.5 (5.9)
5	0.6b (1.5)	0.5b (1.2)				0.3	2.1b (2.6)	2.9 (6.1)
6			n/a	0.2		n/a		n/a

Abbreviation: n/a: not applicable.

Weighted frequency (frequencies within each attribute levels do not necessarily add up to a total because of rounding of weighted frequencies).

^aLevels 2–6 for speech and dexterity, levels 5 and 6 for ambulation, and levels 3–5 for emotion.

^bLevels were collapsed because of confidentiality concerns.

For 18+ at baseline, 22.6% of subjects reported no attributes affected whereas the prevalence of one, two, three, four, five, and six or more attributes affected was 37.7%, 24.3%, 10.7%, 3.5%, 1.0%, and 0.2%, respectively. In general, there was relatively little association among the single-attribute HUI3 scores. Among the 28 pair wise comparisons, classifying correlations of <0.10 as negligible, 0.10–0.29 as small, 0.30–0.49 as medium, and ≥0.50 as large [35], the observed correlations (all statistically significant) were negligible in 10 cases, small in 17 cases, and large in one case. The minimum correlation observed, 0.04, was between vision and emotion; the maximum observed, 0.32, was between ambulation and pain. The correlation between hearing and ambulation was 0.11. For the 60+ cohort at baseline, 5.6% of subjects reported no attributes affected whereas the prevalence of one, two, three, four, five, and six or more attributes affected was 31.3%, 29.2%, 17.6%, 8.1%, 3.5%, and 3.9%, respectively.

Results from the Cox proportional hazards model for the 18+ cohort were consistent with a priori expectations and results from previous studies. Being widowed, being male, less than the highest level of income, less than a high school education, being underweight, and smoking were associated with an elevated risk of mortality (Table A1). Further, as expected, the HRs rose sharply with age, especially for those over 60. The HR was importantly higher for those with a life-limiting chronic condition and for the physically inactive. The number of attributes affected also was statistically significant. The bottom rows of Table A1 and Table 4 show negative twice the log likelihood (a crude goodness of fit measure) for the several models. The values are quite similar to each other with the exception of that for ambulation.

Table 4.

Relative hazard of death by selected HUI3 attributes for 18+ and 60+ at baseline

Hazard ratio	Hearing 18+	Hearing 60+	Ambulation 18+	Ambulation 60+	Pain 18+
	0.18 (0.06–0.57)a	0.14 (0.04–0.48)a	0.10 (0.04–0.23)b	0.11 (0.04–0.30)c	0.53 (0.29–0.96)c
−2LL (df = 38); P < 0.05	18,721	12,491	18,704	12,483	18,723

Abbreviations: −2LL, twice negative log likelihood; df, degree of freedom.

Complete results are reported in Tables A1 and A2 (for 18+ and 60+, respectively).

^aP < 0.01.

^bP < 0.001.

^cP < 0.05.

For each attribute there was an inverse relationship between the single-attribute utility score and risk of mortality (Table A1). The results for hearing, ambulation, and pain were statistically significant (Table 4). Results are only partially consistent with our a priori expectations. As predicted, ambulation and pain were predictive of mortality; however, cognition and emotion were not. Impaired hearing has not previously been found to have a clear association with mortality.

Results were largely similar for the 60+ cohort (Table A2). Ambulation and hearing are predictive of mortality. The result for pain and discomfort is no longer statistically significant (Table 4).

Results of the simulations performed to illustrate the mortality impact of deficits in hearing, ambulation, and pain for 18+ and hearing and ambulation for 60+ are presented in Table 5. Disability in hearing showed a stepwise and strong impact on mortality. Disability in ambulation was associated with a stepwise increase in morality from level 1 (no disability) to levels 5 and 6 (severe disability) that was substantial and statistically significant. Pain showed a milder, though still statistically significant, impact on mortality in the 18+ cohort but was not statistically significant in the 60+ cohort.

Table 5.

Simulations of the effects of each level for hearing, ambulation, and pain on the relative risk of mortality based on results for 18+; simulations for hearing and ambulation based on results for 60+ in parentheses

Level	Hearing	Ambulation	Pain
1	1.00 (1.00)	1.00 (1.00)	1.00
2	1.27 (1.31)	1.48 (1.45)	1.05
3	1.63 (1.76)	2.15 (2.06)	1.16
4	2.41 (2.75)	4.41 (4.07)	1.39
5	3.16 (3.76)	7.02 (6.30)	1.89
6	5.44 (7.00)	10.12 (8.95)	n/a

Note: For hearing, ambulation, and pain level 1, no disability; level 2, mild disability; level 3, moderate disability (as does level 4, for hearing); levels 5 and 6, severe disability for hearing; levels 4–6, severe disability for ambulation; and levels 4 and 5, severe disability for pain.

4. Discussion

In this large, population-based study with 12 years of follow-up, impaired ambulation, impaired hearing, and pain (only for 18+) were predictive of mortality. Contrary to our a priori predictions, cognition and emotion were not predictive of mortality and hearing was.

It is important to compare our results with previously reported findings. Disability in HUI3 ambulation was associated with increased risk of mortality in a stepwise and substantial fashion for both the 18+ and the 60+ cohorts. Given that HUI3 ambulation is an indicator of physical health, this result is not surprising. Many studies, controlling for an array of confounders, have linked physical health and mortality. Baseline scores from the Health Assessment Questionnaire [36,37], a measure that includes physical functioning, have found it to be predictive of subsequent mortality in patients with rheumatoid arthritis [28,36,38–42], coronary disease [43], those who perceive themselves as being disabled [44], the elderly [45], in a cohort of nurses [8], and in the general population [46].

Lee et al. [47] found that baseline physical activity and cognition were predictive of mortality; see also ref. [48]. Hebert et al. [49] found that restrictions in mobility and cognitive impairment were predictive of mortality. In an analysis of data pooled from nine cohort studies, Studenski et al. [50] found that baseline gait speed was predictive of survival. Tsai et al. [51] found that both the physical health and the mental health summary scores of the Short Form-36 [52] were predictive of mortality; see also refs. [53–58].

That baseline hearing was predictive of subsequent mortality has not been widely reported. Barnett and Franks [59] using data from the National Health Interview Survey report that postlingual (after the acquisition of speech and language) onset of deafness elevated the risk of mortality but that after adjustment for other determinants of health, hearing loss was no longer statistically significant. Appollonio et al. [60,61] using data on a cohort of elderly Italians (70–75 at baseline) found that hearing impairment was predictive of mortality in males. Of course, hearing loss is associated with the aging process [62].

Other studies have reported on the relationship between vision and hearing impairment and mortality. Reuben et al. [63] reported that vision and hearing impairment is a risk factor for mortality and that hearing impairment is predictive of functional decline; see also refs. [64–70].

A number of studies report that hearing impairment is predictive of decline in health status and the onset of functional dependence [71,72] and the onset of anxiety [73]. Brennan et al. [74] using data from the Statistics Canada Participation and Activity Limitation Survey reported that impaired hearing is associated with age, inversely related to education, and associated with limitations in mobility, agility, and pain. Uhlmann et al. [75] report an association between hearing impairment and cognitive dysfunction. Lin et al. [76] using data from the Baltimore Longitudinal Study of Aging found that hearing loss was predictive of the incidence of dementia. Gates et al. [77] report that central auditory dysfunction predicts the onset of Alzheimer Disease. Hearing impairment is related to an elevated risk of falls [78–80]. Schneider et al. [81] report an association between impaired hearing and impaired mobility. Occupational and recreational exposure to noise and smoking is related to hearing loss [82]. Hearing loss also is related to family history [83] and a number of chronic conditions, including cardiovascular ones [84].

There is relatively little evidence on the relationships between pain and mortality. Andersson [85] using data from a Swedish cohort study reports an association between chronic pain and mortality but that when the full range of the determinants of health were controlled for, pain became statistically insignificant. It could be that pain is predictive of mortality in this study because it is a marker for the severity and/or duration of chronic conditions and health problems.

There are several limitations to the findings of our study. First, the power to detect an association between severe levels of disability within each attribute and mortality was limited by the small number of observations in levels, such as levels 5 and 6 (Table 3) and the limited number of deaths during the follow-up period. Limited power may account for the lack of statistically significant results for cognition and emotion, two of our a priori hypotheses. Similarly, lack of power did not allow us to perform gender-based analyses; rather gender was included as an independent variable in the analyses. A second limitation is that there may be measurement error associated with self-reporting on the ability to hear. A number of studies, however, report satisfactory agreement between self-report and results based on audiometry [86–89]. Further, there is evidence for the validity of the HUI3 hearing attribute. HUI3 hearing was able to detect hearing loss associated with the use of cisplatin, an ototoxic platinum compound, in the treatment of neuroblastoma in children [90]. A third possible limitation is that the results reported here are based on data from a representative sample of the community-dwelling population aged 18+ at baseline. Predicting subsequent mortality may be “easier” in cohort studies of patients already diagnosed with a particular disease or in cohorts of older individuals [8]. However, it is notable that baseline overall HRQL and single-attribute scores for hearing, ambulation, and pain are predictive of mortality in a cohort without the “selection bias” associated with being diagnosed with a health problem or being older.

There are several possible explanations for the association between hearing impairment and mortality. First, hearing impairment may increase the risk of accident and injury [79,91–93]. Second, impaired hearing may be a marker for neurological decline [29,76,77,84,94] not captured by typical cognition scales that focus on memory and problem solving. It also is possible that declines in cognitive functioning, resulting in attenuated communication and language comprehension, are interpreted as hearing problems rather than being ascribed to cognition [67]. Poor comprehension may be an early marker of cognitive decline and aging [75,95]. Third, impaired hearing may adversely affect communication and social interaction and the resulting social isolation may lead to declines in physical and mental health [76,95–101]. Fourth, impaired hearing and deafness are associated with less educational achievement, lower rates of employment, a lower likelihood of a managerial or professional occupation, and lower income [92]. Using data from the 2000/01 Canadian Community Health Survey in which hearing was assessed by HUI3, Woodcock and Pole [92] note that those with any impairment in hearing were more likely than those without any hearing impairment to experience a high level of work stress and symptoms of depression; see also ref. [102]. Fifth, in some cases deafness may be the consequence of systemic disease (some brain tumors) or their treatment (platinum compounds used in the treatment of some cancers) [90]. Unsurprisingly, at baseline the prevalence of any hearing impairment was the highest in those 70 years of age or older (21%) and 72% of deaths were 70+ at the time of death. Further research is needed to identify the mechanism(s) through which hearing loss increases the risk of mortality.

The novel finding in our study that disability in hearing is associated with increased mortality may have important clinical and public health implications, especially given the prevalence of hearing loss [103]. Yueh et al. [98] discuss the recommendations for screening for hearing loss released by various agencies and organizations, including the 1996 United States Preventive Services Task Force (currently under review) and the 1994 Canadian Task Force on Preventive Health Care. They note both the underdetection and the undertreatment of hearing problems. Screening for impaired hearing is routine in older age groups but may also be indicated for younger people, especially if they have occupational or recreational noise exposure. More steps to reduce noise exposure in these settings might result in improved HRQL and increased longevity. And for those with impaired hearing, reducing barriers to access to assistive devices or cochlear implants may ensure the least harm from impaired hearing. Cheng and Niparko [104], Francis et al. [105], and Damen et al. [106] provide evidence of substantial gains in HRQL associated with cochlear implants. Mulrow et al. [107] reported gains in HRQL at the 4-month follow-up assessment for those randomized to receive a hearing aid right away whereas HRQL was stable in the group randomized to wait (see also refs. [89,98,101,108]). Stark and Hickson [109] report gains in hearing/communication-specific HRQL in those receiving hearing aids and that gains also were experienced by their significant other. Hawkins et al. [110] document HRQL burdens associated with hearing impairment. Strategies to increase adherence to the use of hearing aids also are important [98].

Further investigations to determine which aspects of health are associated with the risk of mortality are warranted. In particular, further investigation about the relative roles of specific deficits vs. the constellation of deficits is needed. Confirmation that specific deficits (such as hearing) are consistently associated with increased mortality can guide the development of targeted interventions likely to enhance longevity.

What is new?

Key message

Health-related quality-of-life instruments, including hearing and pain, predict mortality (controlling for standard risk factors and health determinants).

What does this study add?

This is the first evidence that two important quality-of-life issues, hearing and pain, predict mortality.

Results also confirm that self-reported mobility predicts mortality.

Implications—what should change now?

These results suggest that more proactive interventions to improve hearing and pain might improve quality-adjusted survival.

Appendix

Table A1.

Relative hazard of death by HUI3 attribute for 18+ at baseline

Independent variables	Vision	Hearing	Speech	Ambulation	Dexterity	Emotion	Cognition	Pain and discomfort
HUI3 attribute	0.57 (0.14–2.30)	0.18 (0.06–0.57)a	0.21 (0.00–215.06)	0.10 (0.04–0.23)b	0.39 (0.09–1.68)	0.31 (0.08–1.14)	0.79 (0.34–1.86)	0.53 (0.29–0.96)c
Number of other attributes affected	1.14 (1.07–1.22)b	1.10 (1.03–1.17)a	1.12 (1.05–1.19)a	1.05 (0.98–1.13)	1.11 (1.04–1.18)a	1.11 (1.04–1.18)a	1.14 (1.06–2.03)b	1.14 (1.03–1.23)a
Male	1.81 (1.56–2.09)b	1.81 (1.56–2.10)b	1.81 (1.56–2.10)b	1.84 (1.58–2.13)b	1.81 (1.56–2.09)b	1.81 (1.56–2.10)b	1.81 (1.56–2.09)b	1.81 (1.56–2.10)b
Age
30–39	1.89 (0.93–3.80)	1.89 (0.94–3.81)	1.89 (0.94–3.81)	1.85 (0.92–3.72)	1.89 (0.94–3.81)	1.90 (0.94–3.85)	1.87 (0.93–3.77)	1.88 (0.93–3.78)
40–49	5.52 (2.80–10.86)b	5.45 (2.77–10.70)b	5.41 (2.76–10.63)b	5.43 (2.78–10.62)b	5.44 (2.78–10.66)b	5.47 (2.77–10.80)b	5.35 (2.73–10.48)b	5.37 (2.74–10.52)b
50–59	14.02 (7.21–27.25)b	13.52 (6.97–26.23)b	13.43 (6.93–26.00)b	13.65 (7.07–26.32)b	13.52 (6.99–26.14)b	13.47 (6.92–26.24)b	13.15 (6.78–25.52)b	13.28 (6.86–25.70)b
60–69	30.45 (15.98–58.01)b	29.24 (15.40–55.52)b	29.13 (15.36–55.24)b	30.27 (16.00–57.24)b	29.43 (15.54–55.77)b	29.25 (15.33–55.82)b	28.57 (15.05–54.24)b	28.86 (15.24–54.66)b
70–79	56.31 (29.24–108.46)b	54.29 (28.33–104.04)b	54.25 (28.30–104.00)b	56.53 (29.50–108.31)b	54.85 (28.63–105.06)b	55.01 (28.55–105.96)b	53.09 (27.61–102.06)b	54.06 (28.20–103.61)b
80+	132.55 (67.18–261.53)b	129.19 (65.98–252.93)b	130.31 (66.36–255.89)b	131.22 (66.93–257.28)b	132.53 (67.62–259.75)b	132.09 (67.09–260.07)b	128.46 (65.17–253.22)b	129.41 (65.74–254.72)b
Marital status
Single	1.28 (0.99–1.63)	1.29 (1.01–1.65)	1.28 (1.01–1.63)	1.27 (0.99–1.62)	1.28 (1.00–1.63)c	1.27 (1.00–1.63)	1.27 (0.99–1.62)	1.28 (1.00–1.63)
Widowed	1.22 (1.01–1.47)c	1.23 (1.02–1.47)c	1.22 (1.01–1.46)c	1.20 (0.99–1.44)	1.22 (1.01–1.46)c	1.21 (1.01–1.46)c	1.22 (1.01–1.47)c	1.22 (1.02–1.47)c
Separated/divorces	0.91 (0.71–1.15)	0.91 (0.72–1.16)	0.91 (0.71–1.15)	0.90 (0.71–1.15)	0.91 (0.71–1.15)	0.90 (0.71–1.15)	0.90 (0.71–1.14)	0.90 (0.71–1.14)
Income
Missing	0.88 (0.57–1.38)	0.89 (0.57–1.39)	0.89 (0.57–1.38)	0.88 (0.57–1.37)	0.89 (0.57–1.38)	0.89 (0.57–1.38)	0.88 (0.57–1.38)	0.88 (0.57–1.37)
Low	1.54 (1.09–2.18)c	1.54 (1.09–2.18)c	1.55 (1.10–2.19)c	1.54 (1.09–2.16)c	1.55 (1.09–2.19)c	1.54 (1.09–2.18)c	1.55 (1.09–2.19)c	1.55 (1.10–2.19)c
Low middle	1.41 (1.02–1.94)c	1.41 (1.02–1.94)c	1.42 (1.03–1.95)c	1.41 (1.03–1.93)c	1.42 (1.03–1.95)c	1.42 (1.03–1.95)c	1.42 (1.03–1.95)c	1.41 (1.02–1.94)c
Upper middle	1.37 (1.00–1.88)c	1.37 (1.00–1.88)c	1.38 (1.01–1.89)c	1.40 (1.03–1.91)c	1.38 (1.01–1.89)c	1.38 (1.01–1.88)c	1.39 (1.01–1.90)c	1.38 (1.01–1.89)c
Education
<High school	1.20 (1.03–1.40)c	1.20 (1.02–1.40)c	1.20 (1.03–1.40)c	1.20 (1.02–1.40)c	1.20 (1.03–1.40)c	1.21 (1.03–1.41)c	1.19 (1.02–1.40)c	1.19 (1.02–1.39)c
High school	1.20 (0.96–1.50)	1.20 (0.96–1.50)	1.20 (0.96–1.50)	1.21 (0.97–1.51)	1.20 (0.96–1.50)	1.21 (0.97–1.51)	1.20 (0.96–1.50)	1.19 (0.95–1.50)
Chronic health conditions
Associated with mortality	1.76 (1.53–2.02)b	1.78 (1.55–2.05)b	1.77 (1.54–2.03)b	1.75 (1.52–2.02)b	1.77 (1.54–2.03)b	1.77 (1.54–2.04)b	1.77 (1.54–2.03)b	1.76 (1.53–2.03)b
Possibly associated with mortality	1.18 (0.90–1.54)	1.19 (0.91–1.55)	1.18 (0.90–1.54)	1.15 (0.87–1.53)	1.18 (0.90–1.55)	1.18 (0.90–1.55)	1.18 (0.90–1.54)	1.16 (0.88–1.52)
Not associated with mortality	1.03 (0.89–1.19)	1.04 (0.90–1.20)	1.04 (0.90–1.20)	1.03 (0.89–1.19)	1.05 (0.91–1.21)	1.05 (0.91–1.21)	1.05 (0.91–1.21)	1.04 (0.90–1.19)
Smoking
Daily smoker	2.27 (1.85–2.78)b	2.30 (1.87–2.82)b	2.28 (1.86–2.79)b	2.29 (1.87–2.81)b	2.28 (1.86–2.79)b	2.28 (1.86–2.79)b	2.27 (1.85–2.79)b	2.25 (1.83–2.76)b
Occasional smoker	1.82 (1.28–2.60)b	1.83 (1.28–2.62)b	1.82 (1.27–2.60)b	1.82 (1.27–2.62)a	1.82 (1.28–2.61)b	1.83 (1.28–2.62)b	1.81 (1.26–2.59)a	1.80 (1.26–2.58)a
Former smoker	1.47 (1.25–1.74)b	1.49 (1.26–1.76)b	1.47 (1.25–1.74)b	1.50 (1.27–1.77)b	1.48 (1.25–1.74)b	1.47 (1.25–1.74)b	1.48 (1.25–1.75)b	1.47 (1.24–1.74)b
Physical activity
Occasional: 4 to 11 times per month	1.05 (0.88–1.26)	1.05 (0.87–1.26)	1.06 (0.88–1.27)	1.05 (0.88–1.26)	1.06 (0.88–1.27)	1.06 (0.88–1.27)	1.06 (0.88–1.27)	1.06 (0.88–1.27)
Infrequent: zero to three times per month	1.27 (1.09–1.47)a	1.28 (1.10–1.49)a	1.28 (1.10–1.49)a	1.25 (1.08–1.46)a	1.28 (1.10–1.49)a	1.29 (1.11–1.49)b	1.27 (1.09–1.48)a	1.28 (1.10–1.48)a
BMI
Underweight (<18.5)	1.71 (1.22–2.41)a	1.71 (1.21–2.40)a	1.71 (1.21–2.40)a	1.59 (1.09–2.32)c	1.71 (1.22–2.41)a	1.69 (1.20–2.38)a	1.69 (1.20–2.38)a	1.70 (1.20–2.40)a
Overweight (25 to <30)	0.82 (0.70–0.95)a	0.82 (0.70–0.95)a	0.81 (0.70–0.94)a	0.83 (0.71–0.96)c	0.81 (0.70–0.95)a	0.81 (0.70–0.94)a	0.82 (0.70–0.95)a	0.82 (0.70–0.95)a
Obese (30 to <35)	0.85 (0.68–1.06)	0.85 (0.68–1.06)	0.85 (0.68–1.06)	0.85 (0.68–1.06)	0.85 (0.68–1.06)	0.85 (0.68–1.06)	0.85 (0.68–1.06)	0.85 (0.68–1.06)
Very obese (≥35)	1.29 (0.93–1.79)	1.29 (0.93–1.79)	1.29 (0.93–1.80)	1.28 (0.92–1.78)	1.29 (0.93–1.80)	1.30 (0.94–1.79)	1.30 (0.93–1.81)	1.29 (0.93–1.79)
Alcohol use
Never drinks	1.16 (0.89–1.51)	1.17 (0.90–1.53)	1.16 (0.89–1.51)	1.17 (0.89–1.52)	1.16 (0.89–1.51)	1.15 (0.88–1.50)	1.15 (0.89–1.50)	1.15 (0.88–1.50)
Former drinker	1.13 (0.91–1.40)	1.14 (0.92–1.42)	1.14 (0.91–1.41)	1.11 (0.89–1.38)	1.14 (0.91–1.42)	1.13 (0.91–1.41)	1.13 (0.91–1.41)	1.12 (0.90–1.40)
<1 drink a day	0.95 (0.79–1.15)	0.95 (0.79–1.15)	0.95 (0.79–1.15)	0.95 (0.79–1.15)	0.95 (0.78–1.15)	0.95 (0.78–1.15)	0.95 (0.78–1.15)	0.95 (0.78–1.15)
≥3 drinks daily	1.22 (0.85–1.74)	1.25 (0.88–1.78)	1.23 (0.86–1.75)	1.17 (0.80–1.70)	1.24 (0.87–1.76)	1.23 (0.87–1.75)	1.23 (0.86–1.75)	1.22 (0.86–1.75)
General chronic stress index	0.94 (0.89–0.99)c	0.94 (0.89–0.99)c	0.94 (0.89–0.99)c	0.94 (0.89–0.99)c	0.94 (0.89–0.99)c	0.94 (0.89–0.99)c	0.94 (0.89–0.99)c	0.94 (0.89–0.99)c
Sense of coherence scale	1.00 (0.99–1.01)	1.00 (0.99–1.01)	1.00 (0.99–1.01)	1.00 (0.99–1.01)	1.00 (0.99–1.01)	1.00 (0.99–1.01)	1.00 (0.99–1.01)	1.00 (0.99–1.01)
Perceived social support index	1.01 (0.93–1.09)	1.01 (0.93–1.09)	1.01 (0.93–1.09)	1.01 (0.94–1.09)	1.01 (0.93–1.09)	1.01 (0.93–1.09)	1.01 (0.93–1.09)	1.01 (0.93–1.09)
Psychological distress scale	1.03 (0.99–1.05)	1.03 (1.00–1.05)c	1.03 (1.00–1.05)c	1.03 (1.00–1.05)c	1.03 (1.00–1.05)c	1.03 (0.99–1.05)	1.02 (1.00–1.05)c	1.03 (0.99–1.05)
−2LL (df = 38); P < 0.05	18,722	18,721	18,727	18,704	18,728	18,727	18,726	18,723

Abbreviations: −2LL, twice negative log likelihood; df, degree of freedom; BMI, body mass index; HUI3, Health Utilities Index Mark 3.

Referent categories are 18–29; married; upper income; more then high school degree; no chronic health conditions; never smoker; regular exercise; and one to two drinks a day. Chronic health conditions associated with mortality: high blood pressure; chronic bronchitis or emphysema; diabetes; heart disease; cancer; and suffered from the effects of a stroke. Chronic health conditions possibly associated with mortality: asthma and Alzheimer Disease or other dementia. Chronic health conditions not associated with mortality: food allergies; allergies other than food allergies; arthritis or rheumatism; back problems excluding arthritis; migraine headaches; sinusitis; epilepsy; stomach or intestinal ulcers; urinary incontinence; cataracts; glaucoma; and other long-term conditions.

^aP < 0.01.

^bP < 0.001.

^cP < 0.05.

Table A2.

Relative hazard of death by HUI3 attribute for 60+ at baseline

Independent variables	Vision	Hearing	Speech	Ambulation	Dexterity	Emotion	Cognition	Pain and discomfort
HUI3 attribute	0.45 (0.10–2.50)	0.14 (0.04–0.48)a	0.03 (0.00–34.5)	0.11 (0.04–0.30)b	0.37 (0.09–1.54)	0.33 (0.05–2.03)	0.80 (0.32–2.01)	0.60 (0.31–1.15)
Number of other attributes affected	1.12 (1.04–1.21)a	1.08 (1.00–1.16)b	1.10 (1.02–1.18)b	1.03 (0.95–1.13)	1.09 (1.01–1.18)b	1.12 (1.03–1.21)a	1.12 (1.02–1.22)b	1.10 (1.01–1.20)b
Male	1.91 (1.86–2.28)c	1.90 (1.06–2.27)c	1.89 (1.59–2.27)c	1.94 (1.62–2.32)c	1.90 (1.59–2.27)c	1.90 (1.59–2.27)c	1.90 (1.59–2.27)c	1.90 (1.59–2.27)c
Age
70–79	1.88 (1.55–2.28)c	1.89 (1.55–2.29)c	1.90 (1.57–2.30)c	1.90 (1.57–2.31)c	1.90 (1.57–2.30)c	1.90 (1.58–2.31)c	1.84 (1.56–2.30)c	1.90 (1.57–2.30)c
80+	4.54 (3.49–5.90)c	4.58 (3.55–5.90)c	4.68 (3.63–6.04)c	4.57 (3.53–5.91)c	4.72 (3.66–6.09)c	4.68 (3.65–6.00)c	4.70 (3.65–6.06)c	4.68 (3.62–6.06)c
Marital status
Single	1.38 (1.02–1.63)b	1.43 (1.06–1.91)b	1.38 (1.02–1.68)b	1.38 (1.02–1.85)b	1.39 (1.04–1.87)b	1.39 (1.02–1.87)b	1.38 (1.03–1.85)b	1.38 (1.03–1.87)b
Widowed	1.21 (0.99–1.48)	1.22 (1.00–1.50)	1.21 (0.98–1.48)	1.19 (0.98–1.46)	1.20 (0.93–1.48)	1.21 (0.99–1.48)	1.21 (0.98–1.48)	1.21 (0.99–1.50)
Separated/divorces	0.85 (0.62–1.17)	0.86 (0.62–1.17)	0.85 (0.62–1.17)	0.85 (0.62–1.17)	0.85 (0.61–1.16)	0.85 (0.62–1.17)	0.84 (0.61–1.15)	0.85 (0.62–1.16
Income
Missing	0.94 (0.54–1.64)	0.49 (0.54–1.65)	0.49 (0.54–1.64)	0.92 (0.53–1.59)	0.94 (0.54–1.64)	0.94 (0.54–1.64)	0.93 (0.53–1.64)	0.93 (0.53–1.63)
Low	1.38 (0.85–2.21)	1.36 (0.85–2.19)	1.38 (0.86–2.22)	1.35 (0.85–2.15)	1.37 (0.85–2.20)	1.37 (0.85–2.19)	1.38 (0.85–2.22)	1.38 (0.86–2.21)
Low middle	1.30 (0.83–2.04)	1.29 (0.83–2.02)	1.30 (0.83–2.04)	1.28 (0.83–1.98)	1.31 (0.84–2.04)	1.30 (0.83–2.03)	1.30 (0.83–2.05)	1.30 (0.83–2.03)
Upper middle	1.32 (0.85–2.07)	1.32 (0.85–2.06)	1.32 (0.85–2.06)	1.35 (0.87–2.08)	1.33 (0.85–2.07)	1.32 (0.85–2.05)	1.33 (0.85–2.08)	1.33 (0.85–2.06)
Education
<High school	1.28 (1.07–1.53)a	1.27 (1.06–1.52)a	1.28 (1.07–1.53)a	1.28 (1.07–1.54)a	1.28 (1.07–1.53)a	1.29 (1.08–1.54)a	1.27 (1.06–1.52)a	1.27 (1.06–1.52)a
High school	1.26 (0.96–1.56)	1.26 (0.96–1.64)	1.26 (0.96–1.65)	1.29 (0.99–1.67)	1.26 (0.96–1.65)	1.27 (0.97–1.66)	1.26 (0.96–1.65)	1.25 (0.96–1.64
Chronic health conditions
Associated with mortality	1.56 (1.34–1.80)c	1.58 (1.37–1.82)c	1.56 (1.35–1.81)c	1.54 (1.33–1.79)c	1.56 (1.35–1.81)c	1.57 (1.35–1.81)c	1.57 (1.36–1.81)c	1.56 (1.35–1.80)c
Possibly associated with mortality	1.12 (0.82–1.51)	1.12 (0.83–1.52)	1.11 (0.81–1.51)	1.09 (0.79–1.50)	1.12 (0.82–1.52)	1.11 (0.82–1.51)	1.11 (0.82–1.51)	1.09 (0.80–1.48)
Not associated with mortality	1.09 (0.93–1.27)	1.10 (0.94–1.28)	1.10 (0.95–1.29)	1.09 (0.94–1.27)	1.10 (0.95–1.29)	1.10 (0.94–1.27)	1.11 (0.95–1.30)	1.10 (0.94–1.27)
Smoking
Daily smoker	1.97 (1.55–2.50)c	2.20 (1.59–2.56)c	1.99 (1.57–2.53)c	1.99 (1.58–2.53)c	2.00 (1.57–2.53)c	2.00 (1.58–2.54)c	1.98 (1.56–2.52)c	1.97 (1.55–2.50)c
Occasional smoker	1.81 (1.19–2.76)a	1.81 (1.19–2.77)a	1.79 (1.17–2.73)a	1.83 (1.20–2.79)a	1.80 (1.18–2.75)a	1.80 (1.18–2.76)a	1.78 (1.17–2.72)a	1.78 (1.17–2.72)a
Former smoker	1.28 (1.28–1.81)c	1.55 (1.30–1.85)c	1.53 (1.28–1.82)c	1.55 (1.30–1.85)c	1.53 (1.28–1.82)c	1.52 (1.28–1.81)a	1.53 (1.28–1.82)c	1.52 (1.28–1.81)c
Physical activity
Occasional: 4 to 11 times per month	1.04 (0.84–1.27)	1.03 (0.84–1.26)	1.05 (0.85–1.28)	1.04 (0.84–1.27)	1.04 (0.85–1.28)	1.04 (0.85–1.28)	1.04 (0.85–1.28)	1.04 (0.85–1.28)
Infrequent: – to 3 times per month	1.32 (1.11–1.58)a	1.34 (1.12–1.60)a	1.34 (1.12–1.60)a	1.31 (1.10–1.57)a	1.34 (1.12–1.60)a	1.33 (1.12–1.59)a	1.33 (1.11–1.59)a	1.33 (1.12–1.60)a
BMI
Underweight (<18.5)	2.08 (1.41–3.07)c	2.12 (1.44–3.11)c	2.10 (1.43–3.09)c	1.94 (1.27–2.95)a	2.09 (1.42–3.08)c	2.09 (1.42–3.08)c	2.08 (1.41–3.00)c	2.07 (1.40–3.06)c
Overweight (25 to <30)	0.79 (0.66–0.96)b	0.80 (0.66–0.96)b	0.79 (0.65–0.95)b	0.80 (0.67–0.97)b	0.79 (0.66–0.95)b	0.80 (0.66–0.95)b	0.79 (0.66–0.95)b	0.79 (0.66–0.95)b
Obese (30 to <35)	0.89 (0.69–1.14)	0.90 (0.71–1.16)	0.89 (0.69–1.14)	0.89 (0.70–1.14)	0.89 (0.69–1.14)	0.89 (0.70–1.14)	0.89 (0.70–1.14)	0.89 (0.70–1.15)
Very obese (≥35)	1.29 (0.83–2.00)	1.30 (0.84–2.01)	1.30 (0.84–2.01)	1.28 (0.84–1.97)	1.30 (0.84–2.01)	1.31 (0.85–2.01)	1.30 (0.84–2.02)	1.29 (0.83–1.98)
Alcohol use
Never drinks	1.16 (0.87–1.55)	1.18 (0.88–1.59)	1.16 (0.86–1.56)	1.17 (0.87–1.57)	1.16 (0.87–1.56)	1.16 (0.86–1.55)	1.16 (0.86–1.55)	1.16 (0.86–1.56)
Former drinker	1.19 (0.91–1.55)	1.22 (0.93–1.59)	1.20 (0.92–1.56)	1.17 (0.89–1.53)	1.20 (0.92–1.57)	1.20 (0.92–1.56)	1.20 (0.92–1.57)	1.19 (0.91–1.56)
<1 drink a day	0.96 (0.75–1.22)	0.96 (0.76–1.22)	0.96 (0.75–1.22)	0.95 (0.75–1.20)	0.96 (0.75–1.22)	0.95 (0.75–1.22)	0.96 (0.75–1.22)	0.96 (0.75–1.22)
≥3 drinks daily	1.28 (0.81–2.03)	1.85 (0.86–2.11)	1.31 (0.83–2.06)	1.19 (0.74–1.92)	1.31 (0.84–2.06)	1.31 (0.83 –2.06)	1.30 (0.82–2.04)	1.31 (0.83–2.06)
General chronic stress index	0.95 (0.89–1.00)	0.95 (0.89–1.01)	0.95 (0.89–1.00)	0.95 (0.90–1.01)	0.94 (0.89–1.00)	0.95 (0.89–1.00)	0.94 (0.89–1.00)	0.95 (0.89–1.01)
Sense of coherence scale	1.00 (0.99–1.14)	1.00 (0.99–1.01)	1.00 (1.00–1.14)	1.00 (0.99–1.01)	1.00 (0.99–1.01)	1.00 (0.99–1.01)	1.00 (0.99–1.01)	1.00 (0.99–1.01)
Perceived social support index	1.03 (0.94–1.09)	1.03 (0.94–1.13)	1.04 (0.93–1.09)	1.04 (0.94–1.14)	1.01 (0.93–1.09)	1.03 (0.94–1.14)	1.01 (0.94–1.13)	1.03 (0.94–1.14)
Psychological distress scale	1.03 (0.99–1.06)	1.03 (0.99–1.07)	1.03 (0.99–1.06)	1.03 (0.99–1.06)	1.03 (0.99–1.05)	1.03 (0.99–1.06)	1.03 (0.99–1.06)	1.03 (0.99–1.07)
−2LL (df = 38); P < 0.05	12,496	12,491	12,499	12,483	12,501	12,498	12,500	12,498

Referent categories are 18–29; married; upper income; more than high school degree; no chronic health conditions; never smoker; regular exercise; and one to two drinks a day. Chronic health conditions associated with mortality: high blood pressure; chronic bronchitis or emphysema; diabetes; heart disease; cancer; and suffered from the effects of a stroke. Chronic health conditions possibly associated with mortality: asthma and Alzheimer Disease or other dementia. Chronic health conditions not associated with mortality: food allergies; allergies other than food allergies; arthritis or rheumatism; back problems excluding arthritis; migraine headaches; sinusitis; epilepsy; stomach or intestinal ulcers; urinary incontinence; cataracts; glaucoma; and other long-term conditions.

^aP < 0.01.

^bP < 0.05.

^cP < 0.001.