Somatosensory and auditory processing in opioid-exposed newborns with neonatal abstinence syndrome: a magnetoencephalographic approach

OBJECTIVE

Opioid exposure during pregnancy is a potential risk factor for the developing central nervous system of the fetus. We studied evoked responses in buprenorphine-exposed newborns who displayed neonatal abstinence syndrome (NAS) to elucidate the possible alterations in functioning of the somatosensory and auditory systems.

METHODS

We compared somatosensory (SEFs) and auditory evoked magnetic fields (AEFs), recorded with magnetoencephalography (MEG), of 11 prenatally buprenorphine-exposed newborns with those of 12 healthy newborns. Peak latencies, source strength and location of SEFs or AEFs were recorded.

RESULTS

AEFs were present in all buprenorphine-exposed newborns without significant differences from those of healthy newborns. In contrast, though no group level differences in SEFs existed, at individual level the response deviated from the typical neonatal morphology in four buprenorphine-exposed newborns.

CONCLUSIONS

Although buprenorphine exposure during pregnancy does not seem to cause constant deficiencies in somatosensory or auditory processing, in some newborns the typical development of somatosensory networks may be - at least transiently - disrupted.

Post-prandial insulin lispro vs. human regular insulin in prepubertal children with Type 1 diabetes mellitus

AIMS

To study whether post-prandial insulin lispro (PL) could be used as a part of insulin therapy instead of premeal human regular insulin (HR) in prepubertal children with Type 1 diabetes mellitus (Type 1 DM).

PATIENTS AND METHODS

In this open, randomized cross-over study patients used either PL or HR at breakfast and at dinner. After a 1-month screening period, patients were randomized to treatment with PL or HR for 3 months and then they crossed over to the other insulin for an additional 3 months. The patients were 24 prepubertal children with Type 1 DM (median age 6.2 years, duration of diabetes 37 months). Home monitoring of 1-day glucose profiles at meals (premeal, 1 h and 2 h after breakfast and after dinner) and HbA1c were measured before randomization, before cross-over, and at the last visit. Data on hypoglycaemic episodes were collected at each of the seven visits. The variables were compared between the two treatments.

RESULTS

Of the patients 22/24 completed the study. There were no major differences in the glucose excursions between PL and HR after breakfast (mean +/- SD: 1-h PL 3.7 +/- 4.7 vs. HR 2.9 +/- 3.9 mmol/l, P = 0.3; 2-h -0.9 +/- 5.4 vs. 0.3 +/- 4.5 mmol/l, P = 0.2, respectively) or after dinner (1-h PL -2.5 +/- 4.8 vs. HR -0.4 +/- 3.7 mmol/l, P = 0.07, 2-h -4.1 +/- 5.2 vs. -0.7 +/- 5.0 mmol/l, P = 0.05, respectively). Mean change of HbA1c was similar in both treatment groups (PL 0.2 +/- 0.8% vs. HR -0.4 +/- 0.7%, P = 0.1). The frequency of hypoglycaemic episodes was 4.9 per patient per month during treatment with PL, and 4.4 during HR (P = 0.3).

CONCLUSION

Treatment with post-prandial lispro as a meal insulin is as effective and safe as traditional treatment with regular insulin in young children.

Abnormal electroencephalogram at diagnosis of insulin-dependent diabetes mellitus may predict severe symptoms of hypoglycemia in children

OBJECTIVES

To evaluate the predictive value of the electroencephalogram (EEG) at the time of diagnosis of insulin-dependent diabetes mellitus (IDDM) for subsequent hypoglycemic coma and/or convulsion. To study whether such an episode causes long-term EEG abnormalities.

STUDY DESIGN

An EEG was recorded in 36 patients with IDDM 2 to 3 weeks after diagnosis (median age, 7.5 years) and was then repeated after an episode of severe hypoglycemia associated with coma and/or convulsion (median age, 13.3 years). Paired EEGs were also recorded in 36 age-matched and IDDM duration-matched control patients who had never experienced severe hypoglycemia. A single EEG was recorded in 36 healthy children, matched with patients' ages at the time of IDDM diagnosis.

RESULTS

Patients with severe hypoglycemia had an abnormal initial EEG recording more often than did control patients with IDDM (22.2% vs 2.8%, P =.03). Each of the healthy children had a normal EEG recording. The odds ratio for risk of subsequent coma and/or convulsion during hypoglycemia in patients with abnormal initial EEG recordings was 8 (95% CI, 1.1-354.7). After such an episode, the frequency of the abnormal EEG recordings was not elevated.

CONCLUSIONS

EEG at the time of diagnosis of IDDM may be useful in identifying those patients at increased risk for coma and/or convulsion as a result of hypoglycemia. However, a single such episode did not appear to have a deleterious effect on the subsequent EEG.

Severe hypoglycaemia in children and adolescents during multiple-dose insulin therapy

Episodes of severe hypoglycaemia, resulting in coma and/or convulsions, were documented in an unselected, population-based group of 376 children and adolescents with Type 1 diabetes mellitus (Type 1 DM) treated at the Aurora Hospital, City of Helsinki. A prospective study in 1994-95 yielded 493 patient-years and a retrospective study in 1990-93, 904 patient-years of data. Of these patients, 77-85% received insulin in three or more daily doses. During 1990-95, 43 patients had a total of 48 severe hypoglycaemic episodes. For each episode (n = 48), one control Type 1 DM patient who had never experienced any severe hypoglycaemia, matched by age, diabetes duration and puberty, was sought from the study population. Incidence of severe hypoglycaemia was 3.1/100 patients years prospectively and 3.6/100 retrospectively. At the time of the episode, median age was 13.3 (range 2.2-21) years, and median diabetes duration 6.1 (0.5-14.6) years. Rates were similar in different age groups (< 6, 6-12.9 and > or = 13 years). A potential explanation for the hypoglycaemia was found in 79% of the episodes. Insulin dose was higher (p = 0.04) and HbA1c lower (p = 0.005) in patients with severe hypoglycaemia than in controls. In conclusion, multiple-dose insulin therapy in young patients with Type 1 DM can be associated with a low rate of severe hypoglycaemia. The majority of such episodes seem to be preventable.

Experience of severe hypoglycaemia may influence both patient's and physician's subsequent treatment policy of insulin-dependent diabetes mellitus

Daily insulin doses and HbA1c were studied 0-3 months before and 2-6, 7-11, and 12-16 months after 48 consecutive episodes of severe hypoglycaemia (coma and/or convulsion) in children and adolescents with insulin-dependent diabetes mellitus. After 69% of the attacks, either physicians or patients or both decreased daily insulin doses (for the whole group, mean SD: 0-3 months before the episode 0.93 0.20 U/kg vs 2-6 months after 0.84 0.20 U/kg, P < 0.001), which may have worsened the subsequent glycaemic control as evidenced by a significant increase in HbA1c (8.3+/-1.5% vs 9.1+/-1.8%, P< 0.001, respectively). Physicians decreased the insulin dose even in 14 of the 33 patients with a preventable cause for their hypoglycaemia other than erroneous excess of insulin.

CONCLUSION

Experience of severe hypoglycaemia may worsen the subsequent glycaemic control. This might in part be due to an excessive lowering of daily insulin doses by both physicians as well as patients and their families. Hypoglycaemia management must include intensive education about prevention without compromising diabetes control.

Documented symptomatic hypoglycaemia in children and adolescents using multiple daily insulin injection therapy

Symptomatic episodes of documented hypoglycaemia were characterized with the aid of a 3-month diary in a single-centre, unselected group of 161 children and adolescents with Type 1 diabetes mellitus, treated mainly (81%) with multiple-dose insulin therapy. Patients and families were asked to write in the diary all the symptomatic episodes in which blood glucose concentration proved to be < or =3 mmol l(-1) before treatment. Of the patients, 83 (52%) had a total of 287 hypoglycaemic episodes (0.6 attack per month per patient). The majority of the attacks, 221 (77%), were mild (patients > or =6 years able to treat themselves). Only two attacks were severe, resulting in coma and/or convulsion. The most common dominant symptoms were weakness (29%), tremor (20%), hunger (14%), and drowsiness (12%). Of all the dominant symptoms, 39% were classified as autonomic, 20% neuroglycopenic, and 41% non-specific. In children under 6 years, autonomic symptoms were less common than in adolescents 15 years or over (34% vs 57%, p = 0.01). In conclusion, the incidence of documented symptomatic hypoglycaemia was low. The symptoms were more often neuroglycopenic or non-specific than autonomic, especially in young children.