G. D. Valk

Quality of care for patients with Type 2 diabetes mellitus—a long‐term comparison of two quality improvement programmes in the Netherlands

Aimu2003 To compare two intervention programmes, aimed at improving the quality of care provided for patients with Type 2 diabetes in the longer term.

'Numbness of the feet' is a poor indicator for polyneuropathy in Type 2 diabetic patients

Aimsu2003To identify neuropathic sensory symptoms associated with a clinical neurological examination (CNE) and to investigate whether these symptoms could be used as a diagnostic or screening tool for diabetic polyneuropathy in general practice.

Methods for assessing diabetic polyneuropathy: validity and reproducibility of the measurement of sensory symptom severity and nerve function tests.

The usefulness of sensory symptoms in the assessment of diabetic polyneuropathy is unclear. In the present study, we studied the hypothesis that pain is associated with small nerve fibre function, and that sensory alteration is associated with large nerve fibre function. In addition, we assessed the reproducibility and the ability to detect changes in clinical status over time of the nerve function tests currently used in clinical trials. Patients (78) with stable diabetic polyneuropathy were examined on three separate occasions with a test-retest interval of 17 and 52 weeks. Small nerve fibre function was measured using temperature discrimination thresholds for warmth (TDTwarmth) and cold (TDTcold). Large nerve fibre function was measured by testing sensory and motor nerve conduction velocities (SNCV and MNCV) and vibration perception thresholds (VPT). Neuropathic pain was only significantly associated with TDTcold, and with the MNCV of the tibial nerve. Sensory alteration was associated with almost all nerve function tests except the SNCV and MNCV of the ulnar nerve. The measurements of symptom severity and the nerve function tests all proved to be sufficiently reproducible. The standardized smallest detectable difference on group level (SDD) of the measurement of sensory alteration and neuropathic pain were almost the same (9% and 12%, respectively). Among the nerve function tests, the SNCV and MNCV had the smallest SDD (3-4%), and were, therefore, potentially the most responsive instruments. The SDD of the TDT was greater than the VPT (9-14% vs 21-28%, respectively). In conclusion, neuropathic pain was not associated with small nerve fibre function, and sensory alteration was associated with both large and small fibre function. In addition, the standardized measurement of symptom severity, the SNCV and MNCV tests, and the VPT test appear to be useful for monitoring the course of polyneuropathy in clinical trials.

Longitudinal assessment of the development of diabetic polyneuropathy and associated risk factors

Aims To longitudinally assess risk factors for diabetic polyneuropathy (DPN) severity, and to longitudinally assess risk factors for the change of DPN severity during 2–4 years of follow‐up.

Complaints of neuropathy related to the clinical and neurophysiological assessment of nerve function in patients with diabetes mellitus

To determine the value of a detailed evaluation of neuropathic sensory complaints in assessing diabetic polyneuropathy, a questionnaire listing different sensory symptoms was compared with a clinical and neurophysiological examination of the peripheral nerves. Thirty-seven insulin dependent and thirty-one non-insulin dependent diabetic patients who were consecutively referred because of suspected polyneuropathy were investigated. In all patients both clinical and neurophysiological examination confirmed the diagnosis of polyneuropathy. Only the scores of the clinical examination were significantly correlated with the scores of the sensory symptoms (r = 0.31, P < 0.01). Using a factor analysis, a dimension of complaints of sensory alteration could be distinguished from a dimension of complaints of neuropathic pain (alpha coefficients 0.88 and 0.86, respectively). Tingling sensations turned out to be an expression of the dimension of complaints of sensory alteration. The scores of clinical and neurophysiological examinations were only significantly correlated with the dimension of sensory alteration (r = 0.38, P < 0.002; r = 0.37, P < 0.02, respectively). We conclude that only symptoms of numbness and tingling sensations in hand and feet are associated with objectively assessed diabetic polyneuropathy.

Hyperhomocysteinaemia is not related to risk of distal somatic polyneuropathy: The Hoorn Study

Abstract. Hoogeveen EK, Kostense PJ, Valk GD, Bertelsmann FW, Jakobs C, Dekker JM, Nijpels G, Heine RJ, Bouter LM, Stehouwer CDA (University Hospital Vrije Universiteit, Amsterdam). Hyperhomocysteinaemia is not related to risk of distal somatic polyneuropathy: The Hoorn Study. J Intern Med 1999; 246: 561–566.

Treatment of diabetic polyneuropathy with the neurotrophic peptide ORG 2766.

The efficacy of the neurotrophic peptide ORG 2766 in diabetic patients with polyneuropathy was evaluated in a double-blind, placebo-controlled, multicentre trial. One hundred and twenty four patients were randomised in five groups to receive 0.1, 0.4, 2 or 5 mg ORG 2766 or placebo, once daily, administered subcutaneously 52 weeks. Thermal discrimination thresholds (TDT) and vibration perception thresholds (VPT), motor and sensory nerve conduction velocity, Hoffmann reflex, heart rate variation during deep breathing and heart rate response after standing up, neurological examination score and neuropathic symptom score were determined at baseline and after 17, 34 and 52 weeks of treatment. Of the nerve function indices studied, at week 52 the TDTwarmth of the hand in the ORG 2766 0.1, 0.4 and 5 mg groups and the TDTcold of the foot in the ORG 2766 0.1 and 0.4 mg groups significantly improved compared with placebo. Further significant improvement as compared with placebo was observed in the paraesthesia score at week 34 and week 52 in the ORG 2766 2 mg group. Only at week 34 had both the heartbeat variation during deep breathing and the VPT of the foot in the ORG 2766 0.1 mg group improved significantly, compared with placebo. No further statistically significant differences were observed at time for the other measures. No adverse reactions were observed. The only recorded drug-induced side effect was pain at the injection site. Taking all measures of efficacy into account, the statistically significant results observed did not show consistency within each measure. Therefore, it is concluded that ORG 2766, in contrast to earlier reports, is not effective in treating diabetic polyneuropathy.