Associations of indicators of sleep impairment and disorders with low muscle strength in middle-aged and older adults: The HypnoLaus cohort study.

OBJECTIVE:Investigate associations of objective and subjective indicators of sleep impairment and disorders with low muscle strength (LMS) in different age groups and genders using data from a population-based cohort study. METHODS:Polysomnographic and subjective sleep data from participants (aged 40-80 years) of the HypnoLaus study (Lausanne, Switzerland) were cross-sectionally analyzed. Indicators of sleep impairment and disorders were based on pre-defined cutoffs. LMS was defined according to the diagnosis of sarcopenia (grip strength <27 kg for men and <16 kg for women). Results obtained by multivariate logistic regression were controlled for confounders. RESULTS:1902 participants (mean [SD] age, 57.4 [10.5] years; 968 [50.9 %] female) were enrolled. Objective short (<6.2 h) and long sleep durations (>8.5 h) were associated with LMS (OR = 1.74, 95 % CI = 1.07-2.82; OR = 6.66, 95 % CI = 3.45-12.87, respectively). Increased nighttime wakefulness >90 min and severe obstructive apnea (OSA) (AHI > 30) were associated with LMS (OR = 1.60, 95 % CI = 1.01-2.56; OR = 2.36, 95 % CI = 1.29-4.31, respectively). In adults aged over 60 years, these associations persisted, and reduced sleep efficiency was associated with LMS (aOR = 1.81, 95 % CI 1.05-3.13). Objective long sleep duration was associated with LMS in both genders and severe OSA predicted LMS among women (aOR = 2.64, 95 % CI 1.11-6.24). CONCLUSIONS:Markers of early sarcopenia are affected by long sleep duration from middle age onwards in both genders. Older adults are more susceptible to the effects of other indicators of inappropriate sleep duration and quality. The findings support a potential role of sarcopenia in age-related OSA. The intricate relationships between sleep and muscle health are potential targets of public health interventions and clinical research on preventive and therapeutic strategies against the increasing morbimortality observed with ageing.