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- Nixon Andréasson, Anna, et al.
(författare)
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Associations between leptin and self-rated health in men and women
- 2010
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Ingår i: Gender Medicine. - : Elsevier BV. - 1550-8579 .- 1878-7398. ; 7:3, s. 261-9
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: As an important mediator by which the brain receives information about the body's energy state, leptin may be associated with subjectively perceived health. OBJECTIVE: The main aim of the present study was to investigate concurrent and prospective associations between leptin and self-rated health (SRH), a strong predictor of morbidity and mortality, in a random population sample. An additional aim was to examine whether sick leave was associated with leptin and poor SRH. METHODS: In a prospective, population-based cohort study in Sweden, men and women underwent a medical examination in 1998, at which time blood was drawn and participants were asked to respond to a questionnaire concerning demographics, health behavior, and psychosocial factors. In 2000, the participants responded to a second questionnaire sent by postal mail. Spearman rank correlations were used to investigate the relationships between leptin, SRH, sick leave, and background variables. Partial Spearman coefficients were then calculated to investigate the patterns of association between leptin, SRH, and sick leave independent of age, body mass index (BMI), presence of diagnosis, and testosterone or estradiol. RESULTS: A total of 98 men and 104 women, aged 23 to 76 years, and 91 men and 96 women at follow-up, participated in the study. In men, relatively higher levels of leptin were prospectively associated with relatively worse SRH (rho = 0.20; P = 0.05), but the relationship was not significant in the cross-sectional analysis (rho = 0.18; P = 0.07). This association was not found in women. When controlling for age, BMI, presence of diagnosis, and testosterone, higher levels of leptin were associated with poor SRH in men in cross-sectional analysis (rho = 0.27; P < 0.01) but not prospectively. In women, leptin was not associated with SRH in cross-sectional analysis, but relatively higher levels were prospectively associated with better SRH when adjusted for background factors and estradiol (rho = -0.26; P < 0.05). SRH was independently associated with future sick leave in both men (rho = 0.34; P < 0.01) and women (rho = 0.30; P < 0.05), whereas no association between leptin and future sick leave was found. CONCLUSIONS: Contrasting associations were found between men and women in the relationship between leptin and SRH. Based on the finding that higher leptin levels were associated with better SRH in women than in men, along with corroboration from recent studies, we propose that leptin may serve different psychobiological functions in men than in women.
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| 2. |
- Nixon Andreasson, Anna
(författare)
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Self-rated health : biobehavioral determinants with focus on inflammatory factors
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Self-rated (subjective) health is an independent predictor of future mortality, but neither the mechanisms behind this relation nor the biological determinants of poor self-rated health are known. Inflammatory cytokines give rise to a sickness response which includes fatigue, malaise, anhedonia and pain, resembling factors that are known to impact negatively on self-rated health. It is therefore possible that cytokines that cause a sickness response are important mediators in subjective health perception. This thesis investigated biobehavioral determinants of self-rated health, with a primary focus on inflammatory cytokines. The study populations included women patients from a primary health care center (Study I), women from a population based study on memory and aging in Umeå (Study II), men and women from a population based prospective study in Stockholm (Study III), and men in a laboratory study on the effects of experimentally restricted sleep (Study IV). A main finding was that higher (or increased) levels of inflammation related cytokines were associated with poor (or deteriorated) self-rated health; interleukin (IL)-1β, IL-1ra and tumor necrosis factor (TNF)-α in study I, and IL-6 in study II and IV. The observed association between higher levels of cytokines and poor self-rated health was shown to be stronger with increased age. Of psychological factors, positive affect turned out to be a more important determinant of self-rated health as compared to negative affect. In study III, the relation between leptin, a cytokine-like marker for available energy in the body, and self-rated health was investigated. Higher levels of leptin were associated to poor self-rated health in men, while instead predicting better future self-rated health in women. Moreover, self-rated health was associated to further sick-leave in both men and women. In study IV, subjective health - framed to represent the prevailing day - deteriorated gradually when sleep was restricted to 4 h per night, and returned to baseline levels after two days of recovery. This decrease in subjective health was significantly correlated with increased levels of circulating IL-6. This thesis presents increased support for an immune component of subjectively perceived health. It also implies that more short-term perspectives, e.g. in relation to changes in health behaviors such as sleep, should be taken into account when understanding subjective health perception. The results are of importance for understanding the psychobiological underpinnings of self-rated health and may give clues to explain its well-established association to future health.
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