LONG-TERM SURVIVORS OF CHILDHOOD-CANCER HAVE AN INCREASED RISK OF MANIFESTING THE METABOLIC SYNDROME

Survivors of childhood cancer have been reported to have a severalfold increased risk of death from cardiovascular disease. A cluster of met abolic abnormalities, including obesity, insulin resistance, hyperinsu linemia, glucose intolerance, hypertension, and dyslipidemia, have bee n designated as forming a metabolic syndrome that is associated with i ncreased cardiovascular mortality. We studied 50 survivors (23 males) of childhood cancer, aged 10.5-31.2 yr, an average of 12.6 yr (range, 7.9-21.3 yr) after their diagnosis and compared them with 50 age- and sex-matched controls for signs of the metabolic syndrome by examining clinical and anthropometric measures, serum lipid profile, and fasting plasma insulin and glucose concentrations. Spontaneous nocturnal GH s ecretion was also evaluated in the cancer survivors. The patients had increased relative weight (P=0.03) and body fat mass (P <0.001), decre ased serum high density lipoprotein (HDL) cholesterol (P <0.001), and a reduced ratio of HDL to total cholesterol (P=0.01). Fasting plasma g lucose and insulin levels were higher (P <0.001 and P=0.003, respectiv ely) in the cancer survivors than in the controls. The patients had an increased risk [odds ratio (OR), 4.5; 95% confidence interval (CI), 1 .3-15.8; P=0.01] of obesity (relative weight, >120%), fasting hyperins ulinemia (>111 pmol/L; OR, 3.0; 95% CI, 1.0-8.6; P=0.04), and reduced HDL cholesterol (<1.07 mmol/L; OR, 7.9; 95% CI, 2.2 to 29.6; P <0.001) . A combination of obesity, hyperinsulinemia, and low HDL cholesterol was seen in eight cancer survivors (16%), but in none of the controls (P=0.01). This high risk group was characterized by reduced spontaneou s GH secretion (P=0.02). Long term survivors of childhood cancer appea r to have an increased risk of manifestations of the metabolic syndrom e. Decreased GH secretion may contribute to these metabolic abnormalit ies.