Table 1.
Characteristics of the studies included in the systematic review.
| Study and Setting | Study Design | Sample Size | Mean Age 1 | (A)Dietary Intake Assessment (B) Pattern Analysis Method (C) Adjustment Variables |
QoL Measure | Results | Study Quality 2 |
|---|---|---|---|---|---|---|---|
| Woo, J. et al. [66] Hong Kong | Cross sectional | 3378 | 72.5 ± 5.2 | (A):FFQ (B): DQI-I with 4 aspects—variety, adequacy, moderation and overall balance: Range 0–94, high scores better quality (C): Age, sex, socioeconomic status and districts |
SF-12 | Better dietary quality is associated with better self-rated physical and mental health. PCS: β = 0.0689 (p < 0.0001) MCS: β = 0.0693 (p < 0.0001) |
moderate |
| Haveman-Nies et al., SENECA [67] Europe (Belgium, Denmark, Italy, The Netherlands, Portugal, Spain and Switzerland) | Longitudinal | 480 | 72.6 ± 1.6 | (A) Diet history (B) Modified Mediterranean score: Range 0–7, high scores indicate better quality. (C): Age, country |
Self-rated health status | No association observed between diet quality and risk of deterioration of health status. Risk of deterioration in health status resulting from low dietary quality: OR (95% CI): Men 1.1 (0.5, 2.3); women 1.4 (0.7, 2.7) |
weak |
| Schlesinger et al. [68] Northern Germany | Cross sectional | 1389 | 69 (64–73) | (A): 112 item web-based FFQ/ (B): Dietary Index: Two indices namely ’favorable‘ and ’unfavorable‘ were generated (C): Age sex and SES |
EORTC QLQ-C30 | Those with a favorable’ diet had a reduced odds of having a low gHRQoL; OR (95% CI): 0.79 (0.63–0.99) | moderate |
| Perez-Tasigchana et al., UAM-cohort, & Seniors-ENRICA [22] Spain | Longitudinal | 2376 | ≥60 | (A):14 item paper-based FFQ (B): Mediterranean dietary pattern index (UAM-MDP): Range −2 to 6, low score indicates less healthy diet. (C): Age, sex, level of education, smoking, BMI, physical activity, comorbidities |
SF-36 (Spanish version) | No significant association between UAM-MDP and PCS and MCS. | strong |
| 1911 | ≥60 | (A): Dietary history-Enrica (B): PREDIMED score: Range 0–14 high scores better adherence MDS :Range 0–9 high scores better adherence (C): Age, sex, level of education, smoking, BMI, physical activity, comorbidities |
SF-12 | Higher PREDIMED score was associated with slightly better PCS score. Compared to those in the lowest tertile, PCS: b = 0.55 (−0.48 to 1.59) for tertile 2, 1.34 (0.21 to 2.47) for tertile 3PREDIMED score not significantly associated with a better MCS score. [/MCS: tertile 2, b = −0.25 (−1.31 to 0.80) and tertile 3, b = 0.56 (−0.58 to 1.71)] |
|||
| MDS not associated with PCS or MCS | |||||||
| Gopinath et al., BMES [69] Australia |
Longitudinal | 895 | 67.1 ± 7.4 | (A): 145 item FFQ (B): Total Diet Score to assess adherence to dietary guidelines for Australian adults: Range 0–20, higher scores better adherence (C): Age, sex, receipt of pension payment, home ownership, admission to hospitals, walking disability, living alone, 5 or more co morbidities, cognitive and visual impairment |
SF-36 and FACT-C | Adherence to dietary guidelines at baseline was associated with significantly better QoL in four domains after 5 years. Participants in the highest vs. lowest quartile of baseline total diet scores had adjusted mean scores 5.6, 4.0, 5.3, and 2.6 units higher in these SF36 domains 5 years later |
moderate |
| Milte et al., WELL [70] Australia | Longitudinal | 2457 | 59.9 (65–55) | (A): 111 item FFQ (B): DGI: Range 0–130 higher scores reflect greater compliance with dietary guidelines RFS: Range 0–49, with higher scores associated with greater diet quality MDS: Range 0–8, higher scores reflecting greater adherence to Mediterranean diet. (C): Model 1: adjusted for age, sex, education and urban/rural location. Model 2: additionally adjusted for smoking and total physical activity. Model 3: additionally adjusted for BMI |
RAND 36 | Older adults with better quality diets report better health-related QoL, with additional associations with emotional wellbeing observed in women. Better diet quality by DGI was associated with better self-reported HRQoL on the physical function (OR = 1.56, 95% confidence intervals (CI): 1.22–1.99), bodily pain (OR = 1.29, CI: 1.01, 1.63), general health (OR = 1.72, CI: 1.36, 2.19), energy (OR = 1.51, CI: 1.19, 1.92), emotional wellbeing (OR = 1.36, CI: 1.08, 1.72) and PCS (OR = 1.46, CI: 1.15, 1.86). |
strong |
| A higher RFS was associated with better HRQoL on the physical function (OR = 1.43, CI: 1.13–1.82), general health (OR = 1.41, CI: 1.12, 1.78), energy (OR = 1.55, CI: 1.22, 1.96) and emotional wellbeing (OR = 1.41, CI: 1.12, 1.77) | |||||||
| MDS score in the top quartile was associated with a better score on the energy scale (OR = 1.53, CI: 1.11, 2.10). An association between MDS and general health was also observed after adjustment for smoking and physical activity (OR = 1.52, CI: 1.11, 2.08) | |||||||
| Zaragoza-marti et al. [71] Spain | Cross sectional | 351 | 71.06 | (A): MEDIS-FFQ (B): MDS: Range 0–9, higher the score higher the adherence (C): Age, hours of physical activity, educational level, BMI, blood cholesterol, blood glucose levels and blood pressure |
SF 12 | Adherence to MD is positively related to both PCS and MCS of SF12 for both sexes. Regression coefficients for the relationship between Mediterranean diet score with women (MCS (0.07, CI:(−0.96–0.23, p < 0.001) and PCS (0.19, CI (0.04–0.34, p = 0.020)) and men (MCS (0.01, CI: −0.12–0.29, p = 0.004 and PCS (0.05, CI: 0.17–0.20, p = 0.060)) |
moderate |
| Veronese et al., Osteoarthritis Initiative [21] United States | Cross sectional (sub study of a large longitudinal study) | 4470 | 61.3 ± 9.2 | (A): 77 item Block brief 2000 FFQ (B): Modified MDS: Range: 0–55 high scores better adherence (C): Age, sex, race, BMI, education, smoking status, total energy intake, Charlson co morbidity index, use of analgesic drugs, annual income |
SF-12 | Higher adherence to med diet is associated with better QOL. Those with higher aMED showed significantly higher PCS (quintile 5: 50 ± 8.5 compared to quintile 1: 47.2 ± 9.8; p < 0.0001) and MCS (quintile 5: 54.5 ± 7.6 compared to quintile 1: 53.2 ± 8.8; p < 0.0001) | moderate |
| Lewis et al. [72] United States | Longitudinal | 265 | 64.5 ± 10.3 (Caucasians)/60.7 ± 10.2 (African American) | (A): 44 item Diet history questionnaire (B): Dietary index scored from −30 to 30 Higher scores better adherence. (C): Age, sex, follow up time, education, Socio economic factors, BMI, alcohol consumption, smoking and physical activity |
SF-12 | Subjects who improved dietary quality exhibited positive changes in QOL-significant changes observed in functional wellbeing (0.14, CI: 0.05–0.07, p ≤ 0.01), functional assessment of cancer therapy-general total score (0.19, CI: 0.01, 0.37, p = 0.04) and Physical composite score of SF12 (0.23,CI: 0.05–0.41, p = 0.01) | strong |
| Alcubierre et al. [73] Spain | Cross sectional | 294 (146 DR and 148 NDR) | No Diabetic retinopathy: 57.9 ± 10.3 | (A) Semi quantitative FFQ 101 items (B): rMED: Range, 0–18 Adherence was rated as low (0–6), medium (7–10) and high (11–18) (C):Adjustments varied for different components of the QoL domain and included age, ethnicity, insulin treatment, retinopathy, diabetes duration another diabetes related factors |
ADDQOL-19 | rMED was significantly associated with HRQOL dimensions of travels, self-confidence, freedom to eat and freedom to drink. rMED > 8, positively associated with self confidence (p = 0.015), freedom to eat 0.839 (p = 0.037) and freedom to drink 1.150 (p = 0.015) | moderate |
| Diabetic retinopathy: 60.5 ± 8.8 | |||||||
| Rifai et al. [65] United States | Randomised controlled trial | 48 | DASH group (60) and comparison group (64) | (A): FFQ/food diaries (B): DASH diet index: Range 0 to 11, with higher scores indicating higher levels of concordance. (C): N/A |
MLHF | Adhering to the DASH diet improved QoL scores at 3 months; improved MLHFQ scores at 3-month follow-up (21 vs. 39; p = 0.006) | strong |
| Sanchez-Aguadero et al. MARK study [74] Spain | Longitudinal | 314 | 61.1 ± 8.4 (35–74) | (A): FFQ with 18 food groups divided into three categories (B): DQI: Range 18–54, with higher scores associated with better diet quality. aMED: Score ≥ 5 meaning good compliance (C): Age, sex, hypertension, dyslipidaemia and Charlson Comorbidity Index |
Spanish version of the SF-12 v.2 | In those at intermediate cardiovascular risk, DQI was directly related to the mental component score (r = 0.127, p < 0.05) and mental health (r = 0.121, p < 0.05), in bivariate analyses | moderate |
| Greater adherence to the Mediterranean diet was associated with higher scores on the SF-12 mental component, social functioning and vitality and DQI showed an association with the mental component score. Bivariate correlation: The Mediterranean Diet (total score) was related to the mental component (r = 0.164, p < 0.01) as well as social functioning (r = 0.172, p < 0.01) and vitality (r = 0.122, p < 0.05). Multiple linear regression: 1.177 point increase in the mental component for each increase of 1 point in the Mediterranean diet adherence score (p < 0.01), Vitality (β = 0.958 and 0.990) and Social Functioning (p < 0.05 and p < 0.01) domains maintained association post adjustments. | |||||||
| Mosher et al., RENEW [75] United States, UK and Canada |
Cross sectional | 641 | 73 ± 5 | (A): 24 h dietary recalls (B): HEI05: Range 0–100 with scores above 80 indicating good diet quality. (C): age, race, level of education, and number of comorbidities |
SF-36 | Diet quality was positively associated with physical functioning (β = 0.10, Ps < 0.005) and vitality (β = 0.095, Ps = 0.01) | moderate |
| Ford et al., GRAS [76] United States | Cross sectional | 4009 | Males: 81.3 ± 4.2, Females: 81.5 ± 4.5 | (A): DST (B): HEI 05: Range :0–100 (<60 considered “unhealthy”, 60–75 “borderline”, and >75 “healthy”) (C): BMI, disease burden, sex, education, age, smoking status, living situation and self-vs. proxy report |
HALex | Poor diet quality, as assessed by the DST, is associated with lower HRQoL. HALex scores were significantly lower for participants with dietary intakes categorized as unhealthy (<60) (0.70, 95% CI 0.69, 0.72, p < 0.05) or borderline (60–75) (0.71, 95% CI 0.70, 0.73, p < 0.05) compared to those scoring in the healthy range (>75) (0.75, 95% CI 0.73, 0.77). | moderate |
| Sameiri et al., Three City Study [77] France | Cross-sectional | 1724 | 76.0 ± 4.9 | (A): 148 item FFQ (B): Mixed method combining hybrid clusters to derive sex-specific dietary patterns. Five dietary patterns were identified in men and women each. (C): Sociodemographic variables, and comorbidities |
Self-rated health status | Men in the “pasta eaters” cluster had greater risk of reporting poor health (odds ratio [OR] 1.91; 95% CI, 1.21–3.01) than the “healthy” cluster. Women in the “biscuits and snacking” cluster (n = 162; 15%) had greater risk of poor perceived health (OR 1.69; 95% CI, 1.15–2.48) compared to “healthy” eaters. | moderate |
1 Age given as Mean ± SD or mean (range) or minimum age (≥) in years; 2 Quality of studies as assessed by Effective Public health Practice Project (EPHPP) quality assessment tool. SENECA Survey in Europe on Nutrition and the Elderly; a Concerted Action; Seniors—ENRICA Study on Nutrition and Cardiovascular Risk in Spain; UAM Universidad Autonoma de Madrid; BMES Blue Mountain Eye Study; MARK Improving interMediAte Risk management; WELL Wellbeing, Eating and exercise for a Long Life; RENEW Reach—out to Enhance Wellness trial; GRAS Geisinger Rural Aging Study. HRQol Health related quality of life; EORTC QLQ-C30 European Organisation for Research and Treatment of Cancer, quality of life core questionnaire; FACT-C Functional assessment of cancer therapy-colorectal; gHRQol Global Health related quality of life; SF12 Short form survey 12; SF36 Short form survey 36; Rand-36 Rand 36 item health survey; ADDQOL-Audit of Diabetes dependent quality of life; MLHF Minnesota Living with Heart Failure Questionnaire; HALeX Health and activities limitation index. FFQ Food Frequency Questionnaire; DASH Dietary Approaches to Stop Hypertension; rMED Relative Mediterranean diet score; MDS Mediterranean diet score; MD Mediterranean diet; PREDIMED Prevención con Dieta Mediterránea; RFS Recommended Food score; DGI dietary guideline Index; DST Dietary Screening Tool; DQI Diet quality index ; aMED Adherence to Mediterranean diet ; PCS Physical component score; MCS Mental component score.