Definition of the Metabolic Syndrome in Non-HIV-Infected Patients
Metabolic syndrome (MetS)-also previously called syndrome X, insulin resistance syndrome, or dysmetabolic syndrome-was defined, according to the WHO [1], by the presence of:
1.
Impaired glucose regulation (either impaired fasting glucose or glucose intolerance or diabetes) or insulin resistance (the HOMA values being in the top quartile)2. With at least two of the following criteria: triglycerides (TG) >1.7 mmol/L (1.5 g/L), high-density lipoprotein cholesterol (HDL) 30 kg/m2 or waist-to-hip ratio (WHR) >0.9 for men and 0.85 for women, albuminuria/ creatinine ratio ≥30 mg/g
A simplified definition was proposed by the NCEP ATP-III guidelines in 2001 modified in 2005 for the level of fasting glycemia [1]. Moreover, a new definition has been proposed by the IDF (International Diabetes Federation) [2] with a limit for the waist circumference lower than that used in the NCEP III definition, which is a necessary factor for the diagnosis (Table 1).
In France, the prevalence of the metabolic syndrome in the general population is about 10 and 7% of adult men and women, respectively, while in the USA it varies from 20 to more than 50% according to the ethnic origin of the subjects.
The main biological components clustered in the metabolic syndrome are linked to the presence of a state of insulin resistance due to an accumulation of visceral fat resulting in visceral obesity, altered glucose tolerance or diabetes, dyslipidemia with decreased HDL, increased small and dense LDL particles, increased TG and increased blood pressure.
| Table 1 Different definitions of the metabolic syndrome | |
| Definitions | |
| OMS (1999) | Glucose intolerance associated with at least 2 of the following abnormalities: - Hyerpertension ≥ 140/90 mmHg - Elevated triglycerides ≥ 1.7 mmol/L and/or decreased of HDL cholesterol < 0.9 mmol/L in men or < 1.0 mmol/L in women - Central obesity waist to hip ratio > 0.90 in men and > 0.85 in women or body mass index > 30 kg/m2 - Micro-albuminuria ≥ 20 pg/min |
| NCEP ATPIII (2005) | At least three criteria of the following: - Abdominal perimeter ≥ 102 cm in men and ≥ 88 cm in women - Triglycerides ≥ 1.7 mmol/L (1.5 g/L) - HDL cholesterol < 1.03 mmol/L (0.4 g/L) in men and < 1.29 mmol/L (0.5 g/L) in women - Systolic arterial pressure ≥ 130 and/or diastolic arterial pressure ≥ 85 mmHg - Fasting glycemia ≥ 5.6 mmol/L (1 g/L) |
| IDF (2005) | Central obesity defined by an abdominal perimeter ≥ 94 cm for men and ≥ 80 cm for European women associated with at least 2 of the following criteria: - Triglycerides ≥ 1.7 mmol/L, (1.5 g/L) or specific treatment - HDL cholesterol < 1.03 mmol/L (0.4 g/L) in men and < 1.29 mmol/L (0.5 g/L) in women or treatment - Systolic arterial pressure ≥ 130 and/or diastolic arterial pressure ≥ 85 mmHg or treatment - Fasting glycemia ≥ 5.6 mmol/L (1 g/L) |
Prevalence According to ATPIII-NCEP Definition
Moreover, a number or other components can be present such as increased uric acid and plasminogen activator inhibitor (PAI)-I levels, steatosis, presence of a syndrome of polycystic ovaries and of sleep apneas. The risks associated with the metabolic syndrome are predominantly of cardiovascular disease (two or three-fold higher) and diabetes mellitus (six to sevenfold).
Other risks are at the liver level, with the occurrence of NASH (non-alcoholic steatohepatitis) and the possible evolution towards cirrhosis.