Painful neuropathy and foot ulceration in diabetic patients

To examine the prevalence of painful symptoms in neuropathic patients with or without foot ulceration. It has been suggested that there are two clinical presentations of sensory diabetic neuropathy with little overlap: painful (acute or chronic) and painless with recurrent foot ulceration.

We examined three groups of diabetic patients matched for age and duration of diabetes--24 without neuropathy on clinical grounds (mean age 56.1 yr [range 38-76 yr], diabetes duration 12.6 yr [0.4-40 yr]), 30 with neuropathy (mean age 55.3 yr [range 21-73 yr], diabetes duration 17.3 yr [range 0.2-61 yr]), and 40 with neuropathic foot ulceration (mean age 58.1 yr [range 41-72 yr], diabetes duration 18.5 yr [range 1-46 yr])--and compared them with 20 healthy subjects (mean age 50 yr [range 37-69 yr]). For evaluation of neuropathy, the neuropathy symptom score, neuropathy disability score, and vibration perception threshold were measured.

No difference existed between the neuropathic and foot ulcer groups in the neuropathy symptom score (4.2 +/- 3.9 [mean +/- SD] vs. 2.5 +/- 2.1, NS) and neuropathy disability score (15.1 +/- 5.7 vs. 16.8 +/- 6.1, NS), but the vibration perception threshold was lower in the neuropathic group (30.1 +/- 13.4 vs. 40.5 +/- 13.8 V, P < 0.001). Painful symptoms (neuropathy symptom score > 3), either in the past or during the time the study was conducted, had been experienced by none of the control subjects, 7 (29%) of the nonneuropathic group, 18 (60%) of the neuropathic group, and 17 (43%) of the foot ulcer group (NS for the last two groups), and were present at the time of examination in 13 (43%) of the neuropathic group and in 13 (33%) of the foot ulcer group (NS in all groups). Duration of symptoms was < 12 mo in 12 (40%) neuropathic and 15 (38%) foot ulcer patients (NS).

We conclude that painful symptoms are frequent in diabetic neuropathy, irrespective of the presence or absence of foot ulceration and that these symptoms can occur at any stage of the disease. These results suggest that there is a spectrum of neuropathic syndromes from the painful to the patients with foot ulceration, and that much overlap exists.