Sleep Disturbances are Underappreciated in Prostate Cancer Survivorship

Abstract

Background:

The prevalence of sleep disturbances among prostate cancer (PCa) survivors, and extent of urologist involvement in sleep care are not well-studied.

Methods:

PCa survivors (n=167) and urologists (n=145) were surveyed about sleep disturbances and survivorship care practices.

Results:

Most PCa survivors had sleep disturbances, including 50.9% with poor sleep quality, 18.0% with clinical/severe insomnia, and 36.5% at high-risk for sleep apnea.

Few urologists routinely screened for sleep disturbances, as recommended in national cancer survivorship guidelines.

Conclusions:

Optimal PCa survivorship care should incorporate screening for sleep disturbances, addressing comorbid factors affecting sleep and referring to sleep medicine when appropriate.

Introduction

Prostate cancer (PCa) diagnosis and treatment may lead to physical, emotional, and psychosocial symptoms that adversely affect sleep. The National Comprehensive Cancer Network (NCCN) Survivorship Guidelines recommend asking sleep screening questions to cancer survivors at regular intervals.[1] No single study has simultaneously investigated sleep disturbances in PCa survivors using validated questionnaires and the degree of screening for sleep disturbances by urologists. We hypothesize that over half of patients suffer from sleep disturbances and most urologists do not routinely assess sleep.

Methods

We electronically administered surveys to PCa survivors assessing demographics and clinical characteristics, including history of sleep disorders and PCa treatment. Surveys contained 4 validated sleep questionnaires (Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), STOP-BANG (sleep apnea risk), and Sleep Hygiene Index (SHI, healthy sleep behavior)). PCa advocacy organizations distributed the surveys via email and Facebook (ZERO/UsToo International, Prostate Cancer Foundation, and Fans for the Cure). Primary outcomes were poor sleep quality (PSQI >5)[2]; clinical or severe insomnia (ISI >14)[3]; and high-risk for sleep apnea (scores >4 for all 8 questions or scores >1 for 4 STOP questions with BMI >35kg/m² or collar size >40cm).[4] Sleep hygiene was examined as a secondary outcome (higher SHI indicates worse sleep habits).[5]

We electronically administered questionnaires to U.S. urologists. The primary outcome was whether they assess sleep disturbances among PCa survivors, as recommended in NCCN guidelines.[1] Provider surveys were distributed through the American Urological Association New York Section and Veterans Affairs Urology Mailgroup.

Fisher’s exact tests, t-tests, Pearson correlation coefficients, and one-way ANOVA were used to examine unadjusted, bivariate associations between patient characteristics and sleep outcomes (PSQI, ISI). The PSQI analysis excluded patients with known sleep disorders. Descriptive statistics were used to analyze provider surveys.

Results

Table 1 describes demographics for 167 patients. The mean age was 65.3 years, most were white, 58.1% were overweight or obese, and 43.7% had advanced stage PCa.

Table 1.

Baseline demographic characteristics of patients with prostate cancer

	Prostate Cancer Patients (N = 167)*
	Mean ± SD
Age (n = 153) *	65.3 (9.3)
	n (%)
Race (n = 151) *
Non-White	15 (9.9)
White	136 (90.1)
Body mass index (n = 157) *
Underweight or healthy weight	60 (38.2)
Overweight or obese	97 (61.8)
Current cigarette smoking (n = 136) *	16 (11.8)
Hazardous drinking habit or alcohol use disorder (n = 135) *	59 (43.7)
Medical comorbidities
Hypertension	71 (42.5)
Heart disease	25 (15.0)
Depression	30 (18.0)
Diagnosis of a sleep condition
Sleep apnea	23 (13.8)
Insomnia	9 (5.4)
Narcolepsy	0 (0.0)
Restless leg syndrome	4 (2.4)
Stage of prostate cancer (n = 148) *
Localized	75 (50.7)
Advanced	73 (49.3)
Treatment type
Radical prostatectomy	72 (43.1)
Radiation	93 (55.7)
Ablative therapy	13 (7.8)
Hormonal therapy	90 (53.9)
Systemic therapy	31 (18.6)
Miscellaneous therapy	26 (15.6)

^*The following variables had missing data: age (n = 14), race (n = 16), BMI (n = 10), current cigarette smoke (n = 31), hazardous drinking habit or alcohol use disorder (n = 32), and stage of prostate cancer (n = 19)

Overall, 13.8%, 5.4%, 2.4% had pre-existing diagnoses of sleep apnea, insomnia, restless leg syndrome, respectively, and 11.4% reported using sleep medications. Validated questionnaires suggested a higher prevalence of sleep disturbances than self-reported diagnoses, including 50.9% of respondents with poor sleep quality, 18.0% with clinical/severe insomnia, and 36.5% at high-risk for sleep apnea.

Younger age (p=0.01 and p<0.01, respectively), current smoking (both p<0.01), hazardous drinking habits/alcohol use disorder (p=0.02 and p<0.01, respectively), advanced stage PCa (p=0.01 and p<0.01, respectively), hormonal therapy (p=0.01 and p<0.01, respectively), and other systemic therapy (p=0.01 and p<0.01, respectively) were significantly associated with poor sleep quality and insomnia severity. Race, BMI, hypertension, heart disease, depression, radical prostatectomy, and radiation therapy were not associated with either PSQI or ISI scores (data not shown).

The average SHI was 13.7 ± 7.2 (range 0-34). The most common unhealthy sleep behaviors were using the bed for things other than sleeping or sex (23.4%); thinking, planning, or worrying in bed (18.0%); using alcohol, tobacco, or caffeine within 4 hours of bedtime or after going to bed (14.4%); doing something that might wake one up before bedtime (13.2%); and staying in bed longer than one should 2-3 times/week (11.4%).

Among 145 urologists from 36 states, 53.1% are general urologists, 32.4% urologic oncologists, 39.3% in academic practice, 27.6% in the Veterans Affairs system, and 31.7% in private practice. Overall, 73.1% and 71.0% never assess sleep quality before or after PCa treatment, respectively, as recommended in national guidelines. Additionally, 91.7% never/rarely use validated sleep surveys; and 71.1% never/rarely discuss recommendations for good sleep hygiene.

Discussion

Our study adds to previous research identifying a variety of sleep disturbances among PCa survivors.[6][7] Roughly half of PCa survivors reported poor quality sleep. This is concerningly high compared to 34% in a community sample of older U.S adults [8]. Additionally, we found that one-third are at high risk for sleep apnea, a condition that can be life-threatening when left untreated, and one that is associated with cardiovascular disease and urological problems (e.g., nocturia, erectile dysfunction).

We also identified potential risk factors for sleep disturbances such as younger age, advanced stage PCa, ADT and other systemic therapy. Potential contributors include both physical (e.g., pain, hot flashes) and psychological factors (e.g., anxiety, depression).[6]

Concerningly, most urologists do not screen for sleep disturbances despite recommendations in national cancer guidelines.[1] If screening reveals sleep disturbances, urologists should assess for and address any comorbid causes (e.g., pain or medications causing insomnia) or consider referral to a primary care physician or sleep specialist. Future research should investigate how to incorporate sleep health assessment into routine clinical practice, with emphasis on high-risk populations.

Limitations of this study include missing data, small sample size, and lack of racial diversity. Generalizability is also limited by the sampling strategy. The true denominator is difficult to ascertain since surveys were distributed online, and selection bias is possible. Additionally, sleep was measured via subjective questionnaires not objective measures, which may differ.[9] Although the PSQI has been validated in cancer patients,[10] future efforts including subjective and objective sleep assessments are warranted. Nevertheless, self-reported sleep disturbances remain important for quality of life and to trigger evaluation for potentially life-threatening disorders such as sleep apnea. Despite these limitations, this study identifies a need for increased clinician screening for sleep disturbances and promotion of sleep health during PCa care.

Conclusion

Sleep disturbances are common among PCa survivors, particularly in advanced disease. Urologists should routinely screen for sleep problems, address modifiable comorbid factors that negatively affect sleep and refer to sleep specialists when appropriate.