Thyroid hormone status and health-related quality of life in the LifeLines Cohort Study.

BACKGROUND: Thyroid disorders are prevalent in Western society, yet many subjects experience limited symptoms at diagnosis, especially in hypothyroidism. We hypothesize that health-related quality of life (HR-QOL) is more severely impaired in subjects with more abnormal thyroid hormone function tests. METHODS: This is a cross-sectional study of Dutch adults participating in the LifeLines Cohort Study between December 2009 and August 2010. In 9491 Western European participants (median age 45 years; 3993 men and 5498 women), without current or former use of thyroid medication, we compared HR-QOL using the RAND 36-Item Health Survey between subjects with normal thyrotropin (TSH) values and subjects with disturbed thyroid hormone status (serum TSH, free thyroxine, and free triiodothyronine). The influence of possible confounders (age, smoking, co-morbidity) on HR-QOL was evaluated as well. RESULTS: Suppressed TSH values (TSH < 0.5 mU/L) were found in 114 (1.2%), while 8334 (88.8%) had TSH within the normal range, 973 participants (10.3%) had TSH between 4 and 10 mU/L, and 70 (0.7%) had TSH > 10 mU/L. Men had a higher HR-QOL than women (70-92 vs. 65-89; p < 0.001), except for the domain "general health" (72 vs. 72; p = 0.692). Men with suppressed or elevated TSH values did not score significantly lower than euthyroid men for any of nine domains of the RAND 36-Item Health Survey. Compared with euthyroid women, women with suppressed TSH scored significantly lower in the domains "physical functioning" (84 vs. 89, p = 0.013) and "general health" (67 vs. 72, p = 0.036). Women with markedly elevated TSH (> 10 mU/L) had a score in all HR-QOL domains that was similar to that of women with normal TSH values. There were no differences in the physical component score and the mental component score between any of the TSH groups. Physical component score and mental component score were mainly determined by smoking status, co-morbidity, and body mass index or waist circumference. CONCLUSIONS: In this population-based study, HR-QOL scores of subjects with suppressed TSH values or markedly elevated TSH values were generally not significantly lower than those of subjects with normal or mildly elevated TSH values.

Reduced insulin-like growth factor-I serum levels in formerly obese women subjected to laparoscopic-adjustable gastric banding or diet-induced long-term caloric restriction.

Life-span extension in laboratory rodents induced by long-term caloric restriction correlates with decreased serum insulin-like growth factor-I (IGF-I) levels. Reduced activity of the growth hormone/IGF-I signaling system slows aging and increases longevity in mutant mouse models. In the present study, we show that long-term caloric restriction achieved by two different interventions for 4 years, either laparoscopic-adjustable gastric banding or reducing diet, leads to reduced IGF-I serum levels in formerly obese women relative to normal-weight women eating ad libitum. Moreover, we present evidence that the long-term caloric restriction interventions reduce fasting growth hormone serum levels. The present study indicates that the activity of the growth hormone/IGF-I axis is reduced in long-term calorically restricted formerly obese humans. Furthermore, our findings suggest that the duration and severity of the caloric restriction intervention are important for the outcome on the growth hormone/IGF-I axis in humans.

Adipokine profile and insulin sensitivity in formerly obese women subjected to bariatric surgery or diet-induced long-term caloric restriction.

To better understand the contribution of the fat mass to the effects of long-term caloric restriction in humans, we compared adipokine profile and insulin sensitivity in long-term calorically restricted formerly obese women (CRW) subjected to different interventions, bariatric surgery, or reducing diet, with age- and BMI-matched obese (OW) and normal-weight women (NW) eating ad libitum. Our key findings are that despite a considerably stronger weight loss induced by bariatric surgery, both long-term caloric restriction interventions improved insulin sensitivity to the same degree and led to significantly lower retinol-binding protein-4 and interleukin-6 serum levels than in OW, suggesting that lowering of these two adipokines contributes to the improved insulin sensitivity. Moreover, serum leptin was considerably lower in CRW than in OW as well as in NW, suggesting that CRW develop hypoleptinemia.