Testosterone but not estradiol level is positively related to muscle strength and physical performance independent of muscle mass: a cross-sectional study in 1489 older men

Objective: To examine the relationship between different measures of testosterone and estradiol (E2), muscle mass, muscle strength, and physical performance; and to test whether the association of sex hormone level with muscle strength and physical performance was independent of muscle mass. Design and methods: A cross-sectional survey on 1489 community-dwelling men older than 64 years of age. Serum levels of testosterone and E2 were measured by mass spectrometry, and sex hormone-binding globulin (SHBG) levels were measured by immunoradioassay. Muscle mass was examined by dual-energy X-ray absorptiometry and physical performance was assessed by hand-grip strength, gait speed, step length and chair-stand test. Results: Appendicular skeletal mass (ASM) was positively associated with total testosterone (TT; P<0.001), free testosterone (FT; P<0.001), and total E2 (P<0.001) but not with free E2 (P=0.102). After adjustment for age, serum SHBG and relative ASM, both TT and FT were significantly associated with grip strength, narrow-walk speed and the composite neuromuscular score. Higher total E2, but not free E2 was associated with lower grip strength (P<0.05) after adjustment for age, FT, SHBG and relative ASM. Conclusions: Testosterone level was related to both muscle mass, strength and physical performance. Total E2 level, though related to muscle mass positively, affected muscle strength adversely in older men

Sleep duration and disturbances were associated with testosterone level, muscle mass, and muscle strength - A cross-sectional study in 1274 older men

Background: Testosterone level follows a circadian rhythm. However, whether sleep duration and disturbances can affect testosterone level, muscle mass, and strength remains unknown. Objective: To examine the relationship of sleep duration and disturbances to testosterone level, muscle mass, muscle strength, and walking speed. Participants and methods: We recruited 1274 community-dwelling men older than 65 years of age. Their early morning testosterone level was assayed by mass spectrometry. A sleep questionnaire was administered to enquire about their reported sleep duration, prolonged sleep latency (>0.5 hour), and subjective insomnia complaint. Muscle mass was measured by dual-energy x-ray absorptiometry. Testosterone level, muscle mass, handgrip strength, and walking speed were tested against sleep duration and disturbances. Results: Testosterone increased with increasing sleep duration up to 9.9 hours, after which it decreased, giving rise to an inverted U-shaped relationship (P for quadratic trend <.05). A similar inverted U-shaped relationship occurred between sleep duration and muscle mass and function. Earlier go-to-bed time, despite being associated with a higher testosterone level (P < .05), was associated with weaker grip strength (P < .05). Earlier wake-up time was associated with higher muscle mass (P < .05) but neither grip strength nor walking speed. Neither prolonged sleep latency nor insomnia was associated with testosterone levels. However, prolonged sleep latency was associated with lower muscle mass (P < .05), weaker grip strength (P < .05), and slower walking speed (P < .001). Insomnia, on the other hand was associated with weaker grip strength (P < .05) and slower walking speed (P < .001) but not muscle mass. Conclusions: Sleep duration and disturbances can affect testosterone level, muscle mass, and its function. Whether optimization of sleep can ameliorate age-associated decline in sex hormone and muscle performance warrants further studies

Development of salient medication reminders to facilitate information transfer during transition from inpatient to primary care: the Delphi process

Objective Transitional care is important to successful hospital discharge. Providing patients with a clear and concise summary of medication-related information can help improve outcomes, in particular, among older adults. The present study aimed to propose a framework for the development of salient medication reminders (SMR), which include drug-related risks and precautions, using the Delphi process.Design Identification of potential SMR statements for 80% of medication types used by older adult patients discharged from geriatric medicine departments, followed by a Delphi survey and expert panel discussion.Settings Medical and geriatric departments of public hospitals in Hong Kong.Participants A panel of 13 geriatric medical experts.Outcome measure A Likert scale ranging from 1 (strongly disagree) to 5 (strongly agree) points, scoring item relevance, importance and clarity. The minimum of 70% consensus was required for each statement to be included.Results The expert panel achieved consensus through the Delphi process on 80 statements for 44 medication entities. Subsequently, the SMR steering group endorsed the inclusion of these statements in the SMR to be disseminated among older adults at the time of discharge from geriatric medicine departments.Conclusions The Delphi process contributed to the development of SMR for older adult patients discharged from public hospitals in Hong Kong. Patient experience with and staff response to the SMR were assessed at four hospitals before implementation at all public hospitals