OBJECTIVE: Male aging is characterized by a decline in testosterone (TS) levels with a substantial variability between subjects. However, it is unclear whether differences in age-related changes in TS are associated with general health. We investigated associations between mortality and intra-individual changes in serum levels of total TS, SHBG, free TS and LH during a ten-year period with up to 18 years of registry follow-up.
DESIGN: 1167 men aged 30-60 years participating in the Danish Monitoring Trends and Determinants of Cardiovascular Disease (MONICA1) study and who had a follow-up examination ten years later (MONICA10) were included. From MONICA10, the men were followed up to 18 years (mean: 15.2 years) based on the information from national mortality registries via their unique personal ID numbers.
METHODS: Cox proportional hazard models were used to investigate the association between intra-individual hormone changes and all-cause, CVD and cancer mortalities.
RESULTS: A total of 421 men (36.1%) died during the follow-up period. Men with most pronounced decline in total TS (<10th percentile) had a higher all-cause mortality risk compared to men within the 10th to 90th percentile (hazard ratio (HR): 1.60; 95% confidence interval (CI): 1.08-2.36). No consistent associations were seen in cause-specific mortality analyses.
CONCLUSION: Our study showed that higher mortality rates were seen among the men who had the most pronounced age-related decline in TS, independent of their baseline TS levels.
age-related changesm shbg
Few other studies have looked at intra-individual declines in TS levels in aging men in relation to mortality, so this is study fills that knowledge gap. It is notable that T levels were measured at baseline, and after 10 years and 18 years of follow-up. Most epidemiological studies only measure T levels once or twice.