Impact of poorly controlled hypertension on healthcare resource utilization and cost

OBJECTIVE

To examine the relation between blood pressure (BP) control and utilization and cost of healthcare resources.

STUDY DESIGN

A retrospective database study of managed care patients in New Mexico from January 1, 1996, to December 31, 1997.

PATIENTS AND METHODS

We stratified 1000 hypertensive patients into categories based on average and maximum BP. Antihypertensive medication use and cost, number of physician visits, and interval between hypertension-related physician visits were determined.

RESULTS

Medication costs increased progressively across all BP categories from lowest to highest, and higher average systolic BP (SBP) was significantly correlated with increased cost (P < .001). There were significant correlations between higher maximum BP and greater number of hypertension-related physician visits (P < .001). Mean number of visits for BP groups was 5.5 for patients with a maximum diastolic BP (DBP) < 85 mm Hg and 10.0 for those with a maximum DBP > or = 100 mm Hg (P < .001). Patients with a maximum SBP > or = 180 mm Hg averaged 9.7 visits, whereas those with a maximum SBP < 120 mm Hg averaged 4.1 visits (P < .001). Both SBP and DBP were significantly correlated with time to next visit (P < .001). Mean visit intervals ranged from 44 days for patients with an SBP < 85 mm Hg to 25 days for those with an SBP > or = 180 mm Hg (P < .001). A similar association was found between DBP and visit interval.

CONCLUSIONS

Poor control of hypertension is associated with higher drug costs and more physician visits. Aggressive treatment might help reduce managed care costs and resource utilization.

Patterns of radial dysmorphology with the VACTERL association in the adriamycin-exposed prenatal rat

The VACTERL association is an acronym for a constellation of abnormalities affecting the spinal column, anus, heart, trachea, esophagus, kidneys, and limbs that are seen in newborns. It has been shown that prenatal rats exposed to Adriamycin demonstrate a similar series of anomalies. It is the aim of this study to characterize the spectrum of limb anomalies in this model. Female Sprague-Dawley rats (N = 18; 14 experimental and 4 control) were used. After mating, pregnant animals received intraperitoneal injections of Adriamycin (2 mg per kilogram) on days 6, 7, 8, and 9 of gestation. Fetuses were recovered on day 21 of gestation. Ten experimental litters (42 fetuses) and two control litters (18 fetuses) underwent skeletal staining with Alizarin Red S stain. Four experimental litters (N = 18) and two control litters (N = 17) underwent histological study including staining for vascular and neural structures. Upper limb anomalies were found in 45% of the experimental animals, all including either hypoplasia or bending of the radius. The ulna was involved in 37% of the affected limbs. There were no isolated ulnar deformities. There were no histological differences noted. The spectrum of upper limb anomalies seen in the Adriamycin-exposed prenatal rat closely approximates, in incidence and morphology, the upper limb deformities seen with the VACTERL association in children. It is a reliable model for use in additional studies of the embryological mechanism by which these defects arise.

Phytonadione therapy in a multiple-drug overdose involving warfarin

We cared for a patient who ingested an unknown amount of acetaminophen with zopiclone and warfarin. The only liver function test that was abnormal was an increased international normalized ratio (INR), which remained elevated despite treatment with subcutaneous phytonadione and a prolonged infusion of N-acetylcysteine. An interaction between acetaminophen and warfarin may have decreased the hepatic metabolism of warfarin. The patient received numerous antibiotics that may have contributed to the increased INR. The prolonged elevation of INR also may have been due to infrequent administration of phytonadione.

Treatment of multiple sclerosis with interferon beta: an appraisal of cost-effectiveness and quality of life

OBJECTIVE

To evaluate the cost-effectiveness of interferon beta-1b (IFbeta-1b) for relapsing-remitting multiple sclerosis (RRMS).

METHODS

Construction of a cost-effectiveness model using published data on IFbeta-1b effectiveness and the natural history of RRMS, and new data on costs and quality of life (QoL) from a sample of 102 patients with RRMS and resident in northern England.

RESULTS

Poorer QoL was found for patients with multiple sclerosis compared with the general population; those who had had a relapse; those with worse states identified by a clinical measure (expanded disability status scale (EDSS)). Relapses have effects over several months. Health state valuations were higher than in the general population. Costs were higher in relapse than remission and for worse EDSS states. IFbeta-1b costs were larger than cost savings. The best cost-effectiveness estimate was pound28 700 per relapse avoided, which is pound809 900 per QALY gained; or pound328 300 per QALY gained allowing for effects of progression over 5 years. Estimates were robust to changes in assumptions.

CONCLUSIONS

The impact of multiple sclerosis on QoL is substantial. Future trials should base outcomes measurement on QoL and be better linked to natural history and cost data. IFbeta-1b produces important occasional short term QoL gains, but small gains in QALYs overall and large additional costs.

A clinical information systems strategy for a large integrated delivery network

Integrated delivery networks (IDNs) are an emerging class of health care institutions. IDNs are formed from the affiliation of individual health care institutions and are intended to be more efficient in the current fiscal health care environment. To realize efficiencies and support their strategic visions, IDNs rely critically on excellent information technology (IT). Because of its importance to the mission of the IDN, strategic decisions about IT are made by the top leadership of the IDN. At Partners HealthCare System, a large IDN in Boston, MA, a clinical information systems strategy has been created to support the Partners clinical vision. In this paper, we discuss the Partners' structure, clinical vision, and current IT initiatives in place to address the clinical vision. The initiatives are: a clinical data repository, inpatient process support, electronic medical records, a portal strategy, referral applications, knowledge resources, support for product lines, patient computing, confidentiality, and clinical decision support. We address several of the issues encountered in trying to bring excellent information technology to a large IDN.

Acoustic analysis of speech through a hearing aid: consonant-vowel ratio effects with two-channel compression amplification

In this study, the consonant-vowel ratio (CVR) changes associated with varying the compression ratio and crossover frequency of two-channel syllabic compression amplification were examined. Consonant-vowel syllables were recorded at 60 and 75 dB SPL input levels to the hearing aid under 13 different amplification conditions: 12 compression conditions and a condition that used linear amplification in both channels. Syllables consisted of voiceless stops, fricatives, and affricates combined with the vowels /a/, /i/, and /u/. Acoustic analysis of the processed syllables indicated that the CVR was generally increased with compression, compared to linear amplification, and that the effects were greatest for amplification with compression in the high-frequency channel. In addition, higher CVRs were obtained when the crossover frequency was raised. Compression in the low-frequency channel had the least effect on CVR. As previous research has indicated that CVR may serve as a cue to the perception of some consonant sounds by people with hearing impairment, the results suggest the need for caution with the application of high-frequency channel compression until the perceptual effects are fully investigated.

Quantitative analysis of MRI signal intensity in new variant Creutzfeldt-Jakob disease

High signal intensity within the posterior thalamus (pulvinar nucleus) has been noted on MRI in patients with new variant Creutzfeldt-Jakob disease (nvCJD). In this study MRI examinations from three patients with proven nvCJD were compared with MRI examinations from a control group of 14 age-matched subjects with no neurological abnormalities. Mean signal intensity from seven target areas (periaqueductal tissue, posterior thalamus, dorsomedial thalamus, anterior thalamus, putamen, caudate head and frontal white matter) was calculated in each case. Absolute signal intensity measurements were not significantly different between the groups. Patients with nvCJD showed significantly higher signal intensity within dorsomedial thalamus, posterior thalamus and periaqueductal region than control patients when these measurements were normalized to the signal intensity of normal appearing white matter. Highly significant differences in posterior thalamus/putamen signal intensity ratio (PPR) and posterior thalamus/caudate ratio (PCR) were observed between the groups. For proton density images, PPR and PCR were greater than 1 for all nvCJD patients and less than 1 for all control patients. Both PPR and PCR are simple to calculate and offer a simple, non-invasive indicator of nvCJD.

Neurology and the kidney

Renal failure is relatively common, but except in association with spina bifida or paraplegia it is unlikely to occur as a result of disease of the CNS. Renal failure, however, commonly affects the nervous system. The effects of kidney failure on the nervous system are more pronounced when failure is acute. In addition to the important problems related to renal failure there are both acquired and genetically determined diseases which may affect the kidney and the brain. Those acquired diseases include the vasculitides, the paraproteinaemias, and various granulomatous conditions (considered in other chapters of Neurology and Medicine). In two of the most commonly encountered genetically determined diseases, Von Hippel-Lindau disease and polycystic kidney disease, location of pathogenic mutations will provide improved screening programmes and, possibly, allow therapeutic intervention. Uraemia may affect both the central and peripheral nervous systems. Whereas the clinical features of uraemia are well documented, the pathophysiology is less well understood and probably multifactorial. Uraemic encephalopathy, which classically fluctuates, is associated with problems in cognition and memory and may progress to delirium, convulsions, and coma. The encephalopathy may initially worsen with periods of dialysis and almost certainly relates to altered metabolic states in association with ionic changes and possibly impaired synaptic function. Renal failure may affect the peripheral nervous system, resulting in a neuropathy which shows a predilection for large diameter axons. This may be reversed by dialysis and transplantation. The myopathy seen in renal failure, often associated with bone pain and tenderness, is similar to that encountered in primary hyperparathyroidism and osteomalacia. Dialysis itself is associated with neurological syndromes including the dysequilibrium syndrome, subdural haematoma, and Wernicke's encephalopathy. Dialysis dementia, which was prevalent during the 1970s, has reduced in frequency with the use of aluminium free dialysate. With the introduction of transplantation and the concomitant use of powerful immunosuppressive drugs, the pattern of neurological problems encountered in renal replacement therapy has shifted. Five per cent of patients develop nerve injuries during renal transplantation, and up to 40% of patients experience neurological side effects from cyclosporine. Furthermore, CNS infections, often fungal in type, have been reported in up to 45% of transplant patients coming to postmortem. The nature of the involvement of neurologists with their nephrology colleagues is therefore evolving.

Yeast adaptation on softwood prehydrolysate

Several strains and genera of yeast, including Saccharomyces cerevisiae D5A, Pachysolen tannophilus, S. cerevisiae K-1, Brettanomyces custersii, Candida shehatae, and Candida acidothermophilum, are screened for growth on dilute acid-pretreated softwood prehydrolysate. Selected softwood species found in forest underbrush of the western United States, which contain predominantly hexosan hemicellulose, were studied. This phase of the work emphasized debarked Douglas fir. The two best initial isolates were gradually selected for improved growth by adaptation to increasing prehydrolysate concentrations in batch culture, with due consideration of nutrient requirements. Microaerophilic conditions were evaluated to encourage tolerance of pretreatment hydrolysate, as well as ethanol product. Adaptation and simultaneous saccharification and fermentation (SSF) results are used to illustrate improved performance with an adapted strain, compared to the wild type.

Standards of laboratory practice: antiepileptic drug monitoring. National Academy of Clinical Biochemistry

Discussion and development of standards for appropriate monitoring led to the following key recommendations for ordering, sampling, and analyzing antiepileptic drugs: Monitoring should usually be done on trough specimens after steady-state has been reached and always with an appropriate medical indication; non-steady-state concentrations may be indicated in selected situations. Monitoring of free phenytoin and free valproic acid is indicated in specific situations and should be done in serum. The metabolite of primidone, phenobarbital, should be measured concurrently with parent drug, but the active metabolite of carbamazepine does not need to be monitored unless the patient is exhibiting an unusual toxic response that cannot be otherwise explained. Assays used for antiepileptic drug monitoring should display a long-term CV of <10% and preferably <5%. Subtherapeutic and supratherapeutic drug concentrations should be investigated on a regular basis as part of a quality assurance process.

Parotid and submandibular sialadenitis treated by salivary gland excision

BACKGROUND

The purpose of the present study was to compare and contrast the clinicopathological features and treatment outcome of chronic sialadenitis involving the parotid and submandibular glands, among patients who were treated by excision of the affected gland.

METHODS

In a series of 88 patients treated over an 8-year period, 47 had parotid sialadenitis and 41 had submandibular sialadenitis. In the parotid group, 63% of patients were symptomatic for longer than 6 months compared with 27% in the submandibular group. Calculi were implicated in the disease process in 24% of patients with parotid sialadenitis, compared with 73% of patients with submandibular disease.

RESULTS

Patients with parotid sialadenitis had superficial (n = 14) or near-total parotidectomy (n = 35), while those with submandibular sialadenitis underwent total gland excision. Complications occurred twice as frequently in the parotidectomy group. The rate of temporary facial nerve weakness was 29% after parotidectomy while marginal mandibular nerve dysfunction occurred after 12% of submandibular excisions. Both procedures were highly effective in permanently relieving the symptoms of sialadenitis.

CONCLUSIONS

Parotid sialadenitis is infrequently associated with stones and tends to run a longer course before surgical intervention is necessary. Submandibular sialadenitis usually presents earlier, is secondary to calculi and requires early intervention.

Persistent vegetative state and brain stem death

Interest in the persistent vegetative state has focused on the accuracy of diagnosis and prognosis. Retrospective studies in both adult and paediatric groups have raised questions about the most appropriate clinical methods to diagnose patients in the vegetative state and about the length of time before recovery from such a state can be regarded as hopeless. Although no absolute answers have been forthcoming, the debate engendered by the work has been informative and the need for further prospective studies is apparent. Following the publication of guidelines on the management of patients in the vegetative state, the views of physicians in the USA and Europe have been sought in relation to ethical problems and, although they highlight some areas of inconsistency, they show the potential for consensus. Clinically, the field of brain stem death is reasonably defined and consistently managed but the search for methods of technical confirmation of diagnosis continues. It is suggested that the use of magnetic resonance imaging and angiography might provide additional confirmatory evidence.

Multiple intracerebral intravascular papillary endothelial hyperplasia

Intravascular papillary endothelial hyperplasia (IPEH) is a rare benign reactive lesion usually found in thrombosed subcutaneous blood vessels. It uncommonly occurs in the central nervous system and may be mistaken for a more malignant type of tumour such as angiosarcoma. We present a first case of multiple IPEH occurring intracranially in a 51-year-old woman. She developed neurological compromises secondary to the mass affect of the haematoma arising from one of the lesions. Prompt surgical evacuation of the haematoma stabilized her condition. Surgical treatment, pathological findings, radiographic characteristics, and a review of the literature are presented.

New variant Creutzfeldt-Jakob disease: neurological features and diagnostic tests

BACKGROUND

In April, 1996, ten cases of Creutzfeldt-Jakob disease (CJD) with an apparently new clinicopathological phenotype were published and it was suggested that these new variant cases (nvCJD) might be causally linked to bovine spongiform encephalopathy (BSE). There have now been 21 cases of nvCJD in the UK and one case in France. We report clinical features and diagnostic test results of the first 14 cases of nvCJD in the UK.

METHODS

Case ascertainment of CJD was mainly by direct referral from neurologists and neuropathologists. Clinical and investigate details were obtained by interview with patients' relatives and by examination of case notes. Ten cases in this report were examined while alive. Prion protein (PrP) gene analysis was carried out with informed consent from the patient or from a relative. The diagnosis of nvCJD was established histologically.

FINDINGS

Eight cases were women. Mean age at onset of symptoms was 29 (16-48) years and the median duration of illness was 14 (9-35) months. All patients had early psychiatric symptoms, most often depression, and 13 were seen by a psychiatrist early in the clinical course. Eight patients developed early sensory symptoms which were persistent and often painful. Neurological signs, including ataxia and involuntary movements, developed in all cases and towards the end of the illness, most had akinetic mutism. The electroencephalogram was abnormal in most patients but typical periodic complexes of CJD were not seen in any case. Cerebral imaging was usually normal or showed non-specific abnormalities; in two cases magnetic-resonance imaging scans showed high signal in the thalamus.

INTERPRETATION

Clinical features in these cases are similar and relatively distinct from other forms of CJD, suggesting that this is a new clinical phenotype consistent with a single strain of infectious agent. There is, however, some overlap with atypical cases of sporadic CJD, and the diagnosis of nvCJD remains dependent on neuropathological confirmation.

Transient focal neurological deficit in sarcoidosis

Sarcoidosis presents only infrequently with stroke or focal neurological deficit and recurrent focal neurological deficit is rarer still. This case report describes a patients presenting with episodic non-fluent dysphasia of abrupt onset occurring during a period of 18 months without evidence of seizure activity or macroscopic granulomatous collection. The case illustrates that the presentation of neurosarcoidosis may mimic classic reversible ischaemic neurological deficit.

Sound movement detection deficit due to a brainstem lesion

Auditory psychophysical testing was carried out on a patient with a central pontine lesion involving the trapezoid body, who presented with a deficit in sound localisation and sound movement detection. A deficit in the analysis of time and intensity differences between the ears was found, which would explain the deficit in detection of sound movement. The impaired detection of sound movement, due to a lesion interfering with convergence of auditory information at the superior olive, suggests this structure to be critical for human sound movement analysis.

The incidence of diabetes mellitus in an English community: a 20-year follow-up of the Whickham Survey

The original Whickham Survey documented the prevalence of diabetes and lipid disorders in a sample of 2779 adults aged 18 years and over, which matched the British population structure. The aim of the 20-year follow-up study was to determine the incidence and natural history of diabetes. Outcomes in terms of morbidity and mortality at follow-up were determined in over 97% of the original population. Ninety-four subjects had been identified and treated for diabetes since the first survey, including 17 subjects identified as having a fasting plasma glucose > or = 7.8 mmol l-1 at follow-up. The incidence of diabetes for the total population was 2.2 1000-1 year-1 (95% confidence interval 1.8, 2.6). The risk factors identified at first survey were corrected for age, cut-off at the 95 centile and entered into a log linear model. Those which strongly predicted development of diabetes in the total population were fasting blood glucose (odds ratio (OR) (with 95% confidence intervals) = 2.3 (1.5, 3.5)) and body mass index (OR = 2.2 (1.5, 3.3)) in men, and fasting blood glucose (OR = 2.6 (1.7, 4.1)) and fasting serum triglyceride (OR = 2.8 (1.8, 4.4)) in women. A logit model has enabled the calculation of the probability of developing diabetes 20 years later. It was the characteristics of becoming older such as obesity, hypertriglyceridaemia, and raised fasting blood glucose, rather than age itself, which were associated with the development of diabetes.