Prescription medications for sleep disturbances among midlife women during 2 years of follow-up: a SWAN retrospective cohort study

Abstract

Objective: To examine the effects of prescription sleep medications on patient-reported sleep disturbances.

Design: Retrospective cohort.

Setting: Longitudinal cohort of community-dwelling women in the USA.

Participants: Racially and ethnically diverse middle-aged women who reported a sleep disturbance.

Interventions: New users of prescription sleep medications propensity score matched to women not starting sleep medications.

Main outcomes and measures: Self-reported sleep disturbance during the previous 2 weeks-difficulty initiating sleep, waking frequently and early morning awakening-using a 5-point Likert scale, ranging from no difficulty on any night (rating 1) to difficulty on 5 or more nights a week (rating 5). Sleep disturbances were compared at 1 year (primary outcome) and 2 years of follow-up.

Results: 238 women who started sleep medications were matched with 447 non-users. Participants had a mean age of 49.5 years and approximately half were white. At baseline, sleep disturbance ratings were similar: medication users had a mean score for difficulty initiating sleep of 2.7 (95% CI 2.5 to 2.9), waking frequently 3.8 (95% CI 3.6 to 3.9) and early morning awakening 2.8 (95% CI 2.6 to 3.0); non-users ratings were 2.6 (95% CI 2.5 to 2.7), 3.7 (95% CI 3.6 to 3.9) and 2.7 (95% CI 2.6 to 2.8), respectively. After 1 year, ratings for medication users were 2.6 (95% CI 2.4 to 2.8) for initiating sleep, 3.6 (95% CI 3.4 to 3.8) for waking frequently and 2.8 (95% CI 2.6 to 3.0) for early morning awakening; for non-users, the mean ratings were 2.3 (95% CI 2.2 to 2.5), 3.5 (95% CI 3.3 to 3.6) and 2.5 (95% CI 2.3 to 2.6), respectively. None of the 1 year changes were statistically significant nor were they different between medication users and non-users. Two-year follow-up results were consistent, without statistically significant reductions in sleep disturbance in medication users compared with non-users.

Conclusions: These analyses suggest that women who initiated sleep medications rated their sleep disturbances similar after 1 and 2 years. The effectiveness of long-term sleep medication use should be re-examined.

Keywords: epidemiology; sleep medicine; therapeutics.

Figure 1

Assembly of the primary study cohort is demonstrated in this figure. The final study cohort was selected based on propensity score matching from the women who were potentially eligible and met selection criteria.

Figure 2

The three panels describe sleep disturbance ratings by medication exposure. Means were calculated based on 5-point Likert scale, where 1=no difficulties on any nights, 2=difficulties on less than one night per week, 3=one to two nights per week, 4=three to four nights per week and 5=five to seven nights per week. Error bars represent 95% CIs. P values at baseline, year 1 and year 2 comparing sleep medication users with non-users were estimated from the Wilcoxon rank-sum test. In panel A, p values for the differences between medication users and non-users for the change between baseline and 1 year=0.19; baseline and 2 years=0.55 and 1 year and 2 years=0.73. In panel B, p values for the differences between medication users and non-users for the change between baseline and 1 year=0.41; baseline and 2 years=0.98 and 1 year and 2 years=0.55. In panel C, p values for the differences between medication users and non-users for the change between baseline and 1 year=0.13; baseline and 2 years=0.46; *1 years and 2 years=0.03 (favouring non-use).