Weight Loss May Stabilize Neuropathy

According to a recent study published in Obesity, successful dietary weight loss in individuals with severe obesity led to stable neuropathy as measured by the primary outcome, intraepidermal nerve fiber density, after 2 years.

Neuropathy is a highly prevalent condition that results in pain, falls, and lower quality of life. Although diabetes has long been known to be the leading cause of neuropathy, obesity has recently emerged as an important risk factor. Furthermore, obesity is likely sufficient to cause neuropathy even in those with normal glucose control. In addition to hyperglycemia and obesity, other individual components of metabolic syndrome have also been shown to be associated with neuropathy:

• Hypertension
• Hypertriglyceridemia
• Low high-density lipoprotein (HDL) cholesterol

Unfortunately, despite multiple potentially modifiable risk factors, the only established disease-modifying therapy for neuropathy is glycemic control, which prevents neuropathy to a much larger degree in type 1 than in type 2 diabetes.

A group of researchers conducted a study to determine the effect of dietary weight loss on neuropathy outcomes in people with severe obesity. A prospective cohort study of participants attending a medical weight-management program was followed. Weight loss was achieved with meal replacement of 800 kcal/d for 12 weeks and then transitioning to 1,200 to 1,500 kcal/d. The coprimary outcomes were changes in intraepidermal nerve fiber density (IENFD) at the distal leg and proximal thigh. Secondary outcomes included:

• Nerve conduction studies
• Michigan Neuropathy Screening Instrument questionnaire and exam
• Quality of Life in Neurological Disorders
• Quantitative sensory testing

Results of the Study

Among 131 baseline participants, 72 (mean [SD] age: 50.1 [10.5] years, 51.4% female) completed 2 years of follow-up. Participants lost 12.4 (11.8) kg. All metabolic syndrome components improved with the exception of blood pressure. IENFD in the distal leg (0.4 [3.3], p = 0.29), and proximal thigh (0.3 [6.3], p = 0.74) did not significantly change. Improvements were observed on the Michigan Neuropathy Screening Instrument questionnaire, two Quality of Life in Neurological Disorders subdomains, and quantitative sensory testing cold threshold.

Thus, the researchers concluded that dietary weight loss was associated with improvements in all metabolic parameters except blood pressure, and both IENFD outcomes remained stable after 2 years. Given that natural history studies reveal decreases in IENFD over time, dietary weight loss may halt this progression, but randomized controlled trials are needed.

Reference

Dietary weight loss in people with severe obesity stabilizes neuropathy and improves symptomatology by Brian C. Callaghan et al. published in Obesity.

https://doi.org/10.1002/oby.23246