Obesity can result in various Disorders and pathologies:
Obesity , as known from various Studies, is an associated cause for increase in morbidity and mortality. There is 50–100% increase in risk of death from all causes compared to normal weight people, mostly due to cardiovascular causes. Mortality rates rise as obesity increases, particularly when obesity is associated with increased intraabdominal fat . Life expectancy of a moderately obese individual could be shortened by 2–5 years, and a 20- to 30-year-old male with a BMI > 45 may lose 13 years of life. It is also apparent that the degree to which obesity affects particular organ systems is influenced by susceptibility genes that vary in the population.
Insulin Resistance and Type 2 Diabetes Mellitus
Obesity is a major risk factor for diabetes, and as many as 80% of patients with type 2 diabetes mellitus are obese.
Hyperinsulinemia and insulin resistance are pervasive features of obesity, increasing with weight gain and diminishing with weight loss . Insulin resistance is more strongly linked to intraabdominal fat than to fat in other depots. The molecular link between obesity and insulin resistance in tissues such as fat, muscle, and liver has been sought for many years.
Major factors under investigation include:
(1) insulin itself, by inducing receptor downregulation;
(2) free fatty acids, known to be increased and capable of impairing insulin action;
(3) intracellular lipid accumulation; and
(4) various circulating peptides produced by adipocytes, including the cytokines TNF- and IL-6, RBP4, and the “adipokines” adiponectin and resistin, which are produced by adipocytes, have altered expression in obese adipocytes, and are capable of modifying insulin action.
Weight loss and exercise, even of modest degree, are associated with increased insulin sensitivity and often improve glucose control in diabetes.
Also read Dieting for weight control : good or bad
- Male hypogonadism is associated with increased adipose tissue, often distributed in a pattern more typical of females.
- In men >160% ideal body weight, plasma testosterone and sex hormone–binding globulin (SHBG) are often reduced, and estrogen levels are increased.
- menstrual abnormalities in women, particularly in women with upper body obesity.
- increased androgen production, decreased SHBG, and increased peripheral conversion of androgen to estrogen.
- may be associated with polycystic ovarian syndrome (PCOS), with its associated anovulation and ovarian hyperandrogenism; 40% of women with PCOS are obese.
- lower body obesity may contribute to the increased incidence of uterine cancer in postmenopausal women with obesity.
- coronary disease – Read on Acute MI
- and congestive heart failure (CHF).
The waist/hip ratio may be the best predictor of these risks.
- Obesity-induced hypertension is associated with increased peripheral resistance and cardiac output, increased sympathetic nervous system tone, increased salt sensitivity, and insulin-mediated salt retention; it is often responsive to modest weight loss.
- Reduced chest wall compliance,
- increased work of breathing,
- increased minute ventilation due to increased metabolic rate,
- and decreased functional residual capacity and expiratory reserve volume
- Severe obesity may be associated with obstructive sleep apnea and the “obesity hypoventilation syndrome” with attenuated hypoxic and hypercapnic ventilatory responses
higher incidence of gallstones, particularly cholesterol gallstones
cancer of the esophagus,colon,rectum,pancreas,liver, and prostate
- Females –
cancer of the gallbladder, bile ducts, breasts, endometrium, cervix, and ovaries.
Bone, Joint, and Cutaneous Disease
- Obesity is associated with an increased risk of osteoarthritis, no doubt partly due to the trauma of added weight bearing and joint malalignment.
- The prevalence of gout may also be increased
- Among the skin problems associated with obesity is acanthosis nigricans, manifested by darkening and thickening of the skin folds on the neck, elbows, and dorsal interphalangeal spaces. Acanthosis reflects the severity of underlying insulin resistance and diminishes with weight loss.
- Friability of skin may be increased, especially in skin folds, enhancing the risk of fungal and yeast infections. Finally, venous stasis is increased in the obese.
Source: Harrison’s Internal Medicine Book