Efficacy of oral iodised oil is associated with anthropometric status in severely iodine-deficient schoolchildren in rural Malawi.

The effect of anthropometric status on the efficacy of an oral supplement of iodised oil (1 ml Lipiodol Ultrafluide, 490 mg I; Laboratoire Guerbet, Aulnay-sous-Bois, France) was examined in 8-10-year-old schoolchildren (n 197) of Ntcheu, a severely I-deficient district of Malawi. The study was a controlled trial using the I concentration of casual urine samples to monitor the I status. The median urinary I concentration increased from 0.15 micromol/l at baseline (51.3 % of children < 0.16 micromol/l, 89.7 % < 0.40 micromol/l, 95.7 % 0.79 micromol/l) to 0.32 micromol/l at 40 weeks (29.1 % of the children < 0.16 micromol/l, 71.0 % < 0.40 micromol/l, 96.1 % < 0.79 micromol/l) while the total goitre prevalence fell from 63 % to 21 %. Variables of efficacy were estimated from a hyperbolic function describing the longitudinal pattern of urinary I excretion after the dose. The I retention and I elimination rate, and the periods of protection from mild (< 0.79 micromol/l) or moderate (< 0.40 micromol/l) I deficiency were obtained for groups of children with differing anthropometric status at baseline. Initial height-for-age and mid upper-arm circumference were not significantly related to efficacy. However, both the I retention and I elimination rate were reduced in children with lower initial weight-for-height. Children with lower skinfold thickness at baseline also had reduced I retention, which resulted in shorter protection periods from recurrent moderate and mild I deficiency. The efficacy of the oral iodised-oil supplement was not related to changes in anthropometric status during follow-up, nor was it related to the consumption of a food supplement of 1610 kJ immediately before the iodised-oil dose. Very low (< 0.16 micromol/l) urinary I concentration, and the presence of goitre at baseline were both associated with higher I retention and elimination rate. Children with goitre at baseline were found to have a prolonged duration of protection against recurrent moderate I deficiency. We conclude that in apparently healthy schoolchildren in I-deficient areas, general anthropometric status has a little influence on the efficacy of oral iodised oil for correcting I deficiency.

Spinal cord stimulation in patients with chronic reflex sympathetic dystrophy.

BACKGROUND: Chronic reflex sympathetic dystrophy (also called the complex regional pain syndrome) is a painful, disabling disorder for which there is no proven treatment. In observational studies, spinal cord stimulation has reduced the pain associated with the disorder. METHODS: We performed a randomized trial involving patients who had had reflex sympathetic dystrophy for at least six months. Thirty-six patients were assigned to receive treatment with spinal cord stimulation plus physical therapy, and 18 were assigned to receive physical therapy alone. The spinal cord stimulator was implanted only if a test stimulation was successful. We assessed the intensity of pain (on a visual-analogue scale from 0 cm [no pain] to 10 cm [very severe pain]), the global perceived effect (on a scale from 1 [worst ever] to 7 [best ever]), functional status, and the health-related quality of life. RESULTS: The test stimulation of the spinal cord was successful in 24 patients; the other 12 patients did not receive implanted stimulators. In an intention-to-treat analysis, the group assigned to receive spinal cord stimulation plus physical therapy had a mean reduction of 2.4 cm in the intensity of pain at six months, as compared with an increase of 0.2 cm in the group assigned to receive physical therapy alone (P<0.001 for the comparison between the two groups). In addition, the proportion of patients with a score of 6 ("much improved") for the global perceived effect was much higher in the spinal cord stimulation group than in the control group (39 percent vs. 6 percent, P=0.01). There was no clinically important improvement in functional status. The health-related quality of life improved only in the 24 patients who actually underwent implantation of a spinal cord stimulator. Six of the 24 patients had complications that required additional procedures, including removal of the device in 1 patient. CONCLUSIONS: In carefully selected patients with chronic reflex sympathetic dystrophy, electrical stimulation of the spinal cord can reduce pain and improve the health-related quality of life.

Effect of intestinal parasite treatment on the efficacy of oral iodized oil for correcting iodine deficiency in schoolchildren.

Oral supplementation with iodized oil for correction of iodine deficiency in a population has advantages over intramuscular injection but the duration of effect is shorter. The relation of intestinal parasite treatment and efficacy of oral iodized oil was examined in an intervention study in 8-10-y-old schoolchildren in Malawi. Severely iodine-deficient schoolchildren with a single parasitic infestation of Ascaris lumbricoides (n = 44), hookworm (n = 42), or Entamoeba histolytica (n = 24) were randomly allocated to receive or not receive treatment before taking a 1-mL oral supplement (490 mg I) of iodized ethyl esters from poppy seed oil. The urinary iodine concentration was measured at various time points after supplementation to define the time intervals before urinary iodine concentrations returned to 0.40 mumol/L, indicating moderate iodine deficiency. Treatment with metronidazole for E. histolytica increased the protection period from 2.0 to 21.0 wk (P < 0.05). For all untreated children together, the duration of effect was 9.2 wk shorter (P < 0.001) than that for their treated peers (16.8 wk). We conclude that intestinal parasitic infestations reduce the efficacy of oral supplementation with iodized ethyl esters by interfering with absorption.

Prevention and control of iodine deficiency: a review of a study on the effectiveness of oral iodized oil in Malawi.

Unfortunately there will always be groups of people who will not have access to iodized salt as a measure for iodine deficiency control. Iodized oil for oral use may be indispensable for them. The conclusions of a study in Malawi on the effectiveness of oral iodized are that the type of iodized oil, goitre, intestinal parasites, sex, adipose tissue, cassava consumption and seasonality are factors which influence the duration of effectiveness of this prophylaxis measure. The study in Malawi used urinary iodine concentration as a measure for iodine status and a hyperbolic function to describe the pattern of urinary iodine excretion after oral dosing. Cumulative frequency distributions of individually assessed durations of effectiveness very conveniently describe the prevalence rate of iodine deficiency after oral iodized oil administration. They are very useful for identifying factors which influence the effectiveness of oral iodized oil and may thus be a tool for optimizing iodized oil programmes.

New model for describing urinary iodine excretion: its use for comparing different oral preparations of iodized oil.

Iodine excretion in urine after oral dosing with iodized oil is influenced by various factors involved in the retention and elimination of iodine by the body. In a study comparing different treatments of severely iodine-deficient schoolchildren from Malawi, a hyperbolic function was found to describe changes in urinary iodine concentration over time more adequately than a simple exponential function. Compared with oil A, comprising ethyl esters of iodized fatty acids, the retention and elimination of iodine from oil B, comprising triacylglycerol esters of iodized fatty acids, were significantly greater. The mean duration of effectiveness of oral iodized oil, based on urinary iodine concentrations > 0.40 mumol/L, was estimated to be 13.7, 9.9, and 52.5 wk for a single dose of iodized oil A (490 mg I), a split dose of iodized oil A (2 x 245 mg I), and a single dose of iodized oil B (675 mg I), respectively. Dividing the dose of oil A into two equal amounts given on consecutive days did not improve its efficacy.

A critical appraisal of goiter assessment and the ratio of urinary iodine to creatinine for evaluating iodine status.

Iodine status can be evaluated by goiter assessment and measurement of urinary iodine concentration in either 24-h urine collections or in casual samples. It is often impossible to make 24-h collections. Therefore, iodine concentration in casual samples is often expressed in terms of urinary creatinine, assuming creatinine excretion to be constant between and within individuals. In this study large inter- and intraindividual variations were observed in the creatinine content of casual samples ranging from 0.6 to 9.87 mmol/L. Further, the urinary iodine-creatinine ratio correlated significantly with the creatinine concentration; Spearman's rank-order correlation coefficient, rs = 0.39 (P < 0.001). If creatinine is a suitable index to correct for variations in iodine excretion, no correlation would be expected. We conclude that the iodine-creatinine ratio in casual urine samples is an unsuitable indicator for evaluating iodine status in areas where large inter- and intraindividual variations in urinary creatinine excretion exist.