Meralgia paresthetica: relation to obesity, advanced age, and diabetes mellitus

Abstract

Objective: To determine the incidence of meralgia paresthetica (MP) and its relationship to diabetes mellitus (DM) and obesity.

Methods: A population-based study was performed within Olmstead County Minnesota, from January 1, 1990, to December 31, 1999. MP incidence and its association with age, gender, body mass index (BMI), and DM were reviewed.

Results: A total of 262 patients with MP, 262 normal controls, and 262 BMI-matched normal controls with mean age of 50 years were identified (51% men). The age- and sex-adjusted incidence of MP was 32.6 per 100,000 patient years, whereas the incidence of MP in people with DM was 247 per 100,000 patient years, 7 times the occurrence of MP in the general population. Of the patients with MP, 28% had DM vs 17% of BMI-matched controls and the majority of people with MP developed DM after the diagnosis of MP. Patients with MP are 2 times more likely to develop DM (odds ratio 2, 95% confidence interval 1.3-3.0, p = 0.0027). The mean BMI of patients with MP (30.1 kg/m(2), obese class I) was significantly higher than that of age- and gender-matched controls (27.3 kg/m(2), overweight). MP incidence increased 12.9 per 100,000 patient years in the hemidecade study period with an associated increase in both BMI (2.2 kg/m(2)) and average age (3 years).

Conclusions: MP is a frequent painful neuropathy associated with obesity, advancing age, and DM. The incidence rate of MP is predicted to increase as these demographics increase in world populations. Because MP associates with DM beyond weight- and age-matched controls, more aggressive counseling of these patients in prevention of DM may be warranted.

Figure 1. Age- and gender-adjusted incidence rates per 100,000 patient years of meralgia paresthetica (MP)

The incidence rate of MP between men and women was not statistically different. The age group of 55–64 years had the highest incidence of MP in both males and females.

Figure 2. Incidence rates increased significantly over the study period from 23.52 per 100,000 patient years in 1990–1994 to 36.38 per 100,000 patient years in 1995–1999 (p < 0.001)

(A) The noted increase correlated with an increase in body mass index (BMI) during the same period. The mean BMI of patients with meralgia paresthetica from 1990 to 1994 was 28.7 kg/m² (overweight), and 30.9 kg/m² (obese class I) from 1995 to 1999 (p = 0.005). (B) Age increase was borderline significant over the study period, increasing an average of 3 years (p = 0.049). Average age was 48 years from 1990 to 1994 and 51 years from 1995 to 1999.

Figure 3. Occurrence of meralgia paresthetica (MP) in relation to body mass index (BMI) calculated as weight in kilograms divided by height in meters squared and diabetes mellitus (DM)

There is strong association between BMI and occurrence of MP. (A) BMIs are plotted against the number of patients with MP. No patients with MP were underweight (BMI <18.5 kg/m²). The lowest BMI was 18.8 kg/m² and the highest was 57.3 kg/m². The mean BMI of all patients with MP was 30.1 kg/m². The mean BMI of patients with MP without DM was 28.8 kg/m², whereas the mean BMI of patients with MP and DM was 33.8 kg/m². (B) The percentage of patients with DM and MP as a proportion of all patients with MP increases as BMI increases in a linear fashion (R² = 0.97).

Figure 4. Meralgia paresthetica (MP) is significantly associated with diabetes mellitus (DM)

Shown on the left is occurrence of DM in patients with MP in this study. On the right are matched controls for equivalent age, gender, and body mass index (BMI). BMI is calculated by weight in kilograms divided by height in meters squared. Among patients with MP, DM was twice as likely to occur compared with their matched controls.