The use of migraine preventive medications among patients with and without migraine headaches.

The aim was to describe the use of and adherence to migraine preventives among insured patients meeting the International Classification of Headache Disorders, 2nd edn (ICHD-II) criteria for migraine headaches. A retrospective, case-control study was conducted using data from a telephone interview linked with health insurance claims data. Subjects were health plan enrollees aged 18-55 years who had incurred at least one encounter between June 2000 and November 2001. Interview responses were used to identify cases meeting the ICHD-II criteria for strict and probable migraine and a random sample of controls. Pharmacy claims data were used to construct measures of use and adherence. Differences in outcomes by adherence status were evaluated using generalized linear models. We identified 2517 cases and 941 controls. Among cases, the prevalence of antidepressant use was 4%, anticonvulsant use was 1.9%, antihypertensive use was 8.9%. Combined use was 13.4% among cases and did not differ significantly from that observed among controls (12.4%). Mean adherence rate between the first and last dispensing during the year was high (88%) and did not differ by migraine status. When the entire 12-month period is considered, adherence was substantially lower (56%). Patients who were adherent between dispensings reported significantly less migraine-related disability and incurred higher prescription drug costs, but did not differ in their total medical care costs. Patients with migraine are unlikely to be users of preventive medications. Among users, few are taking preventive medications continuously. Patients with migraine-especially those without a medical diagnosis for migraine or headaches-are not receiving the benefits available from existing pharmacotherapy options.

Cost-effectiveness of single-dose methotrexate compared with laparoscopic treatment of ectopic pregnancy.

OBJECTIVE: To evaluate the cost-effectiveness of treatment with intramuscular (IM) methotrexate compared with fallopian tube-sparing laparoscopy for small unruptured ectopic pregnancy. METHODS: A decision-analytic model accounting for varying resolution rates, complication rates, and cost estimates was built to compare the use of methotrexate with laparoscopy. Meta-analysis results of studies identified by a MEDLINE search for IM methotrexate resolution rates and tube-sparing laparoscopy resolution rates were used in model estimation. A similar process was used to generate model complication rates. Data on associated resource use were derived from established clinical guidelines. Estimates of 1998 costs incurred by provider organizations were calculated using data from a large managed care organization. RESULTS: The average methotrexate resolution rate among the studies included was 87% (range 75-90%). The average laparoscopy resolution rate was 91% (range 72-100%). Complication rates for methotrexate ranged from 0% to 22%, with an average of 10% for minor complications, and from 0% to 11% for serious complications, with an average of 7%. Complication rates for laparoscopy ranged from 0% to 8% for intraoperative complications, with an average of 2%, and from 0% to 15% for postoperative complications, with an average of 9%. Baseline model estimates indicated an average cost saving of more than $3000 per resolved ectopic pregnancy with methotrexate treatment compared with laparoscopy. Results of extensive sensitivity analyses supported the finding of a cost saving with methotrexate treatment. CONCLUSION: Single-dose methotrexate is a cost-saving, nonsurgical, fallopian tube-sparing treatment for ectopic pregnancy.

Innovative strategies using SUDAAN for analysis of health surveys with complex samples.

Large-scale health surveys provide a wealth of information for addressing problems in health sciences research. Designed for multiple purposes, these surveys frequently have large sample sizes and extensive measurements of demographic and socioeconomic characteristics, risk factors, disease outcomes and health care service use and costs. Complex features of the sampling design typically employed to select the survey sample, coupled with the vast amount of information available from the survey database, underlie issues that must be addressed during data processing and analysis. Numerous articles in the literature have focused on the debate of whether or not, and how, to control for features of the sample design during data analysis. Traditional statistical methods for simple random samples and the software that accompanies them have historically not had the capacity to account for the survey design. Recent advancements in statistical methodology for survey data analysis have greatly expanded the analytical tools available to the survey analyst. Commercial software packages that incorporate these methods offer the analyst convenient ways for applying such tools to large survey databases in an easy and efficient manner. We present an overview of analysis strategies for survey data and illustrate their application via the SUDAAN software system. Examples for analyses are provided through data from two large US health surveys, the National Health Interview Survey and the Longitudinal Study of Aging. Questions of both a cross-sectional and longitudinal nature are addressed. The examples involve logistic regression, time-to-event analysis, and repeated measures analysis.

Patterns of medical diagnosis and treatment of migraine and probable migraine in a health plan.

The objectives of this study were to assess the proportion of subjects with strict migraine (SM, migraine with and without aura), probable migraine (PM), and all migraine (AM, SM and PM pooled together), who receive a medical diagnosis or a specific treatment within a health plan. Eligible participants were 18-55-year participants of a non-profit health maintenance organization (HMO) who had received out-patient, emergency department, or in-patient care from a physician within the past year. We used a validated computer-assisted telephone interview (CATI) survey to identify SM, PM and controls (received out-patient, emergency department, or in-patient care from a physician for any reason within the past year, but did not have SM or PM). Medical and prescription drug claims for the 24-month period were linked to participant files. Among 8579 respondents, we identified 1265 SM sufferers and 1252 PM sufferers, which were compared with 960 randomly selected controls. Just 194 (15.3%) SM, 21 (1.7%) PM, and 215 (8.5%) AM sufferers received an in-patient or out-patient primary migraine claim in the previous 24 months, compared with six (0.5%) controls; 240 (18.9%) SM, 39 (3.1%) PM, 279 (11.1%) AM sufferers, and eight controls (0.6%) received any migraine claim. There were claims for migraine drugs (ICD-9 code for triptans or ergot compounds) for just 140 (11.1%) SM and 34 (2.7%) PM sufferers, and migraine analgesics (butalbital and isomethepthene compounds), for 6.3% SM and 2.2% PM sufferers (0.7% of the controls). Migraine preventives were used for a larger number of SM and PM sufferers (19.6% and 13.1%), but also for controls (10.5%), indicating that they were probably used for other medical reasons. Both SM and PM are underdiagnosed and undertreated within a health plan. Educational strategies should focus on physician education addressing diagnosing the full spectrum of migraine and physician management of migraine with specific migraine therapy in appropriate patients.

Patient characteristics and costs associated with dyslipidaemia and related conditions in HIV-infected patients: a retrospective cohort study.

BACKGROUND: Metabolic abnormalities are common in HIV-infected individuals and, although multifactorial in origin, have been strongly associated with antiretroviral therapy. METHODS: Using automated claims and clinical databases, combined with medical record data, we evaluated the burden of dyslipidaemia (DYS) and associated metabolic abnormalities among a cohort of 900 HIV-infected patients aged 18 years and older who received their care from a large multispecialty medical group between 1 January 1996 and 30 June 2002. A Cox proportional hazards model for DYS was developed. Resource use was compiled and subsequently costed with stratification to account for variable length of follow-up. RESULTS: Mean follow-up time was 3.3 years. DYS was present in 54% of the cohort and 3.4% experienced a cardiovascular (CV) event. Both unadjusted and adjusted results found patients with dyslipidaemia and cardiovascular events significantly more likely to have received protease inhibitor (PI) treatment for longer periods of time. In the Cox proportional hazards model the following factors were significantly associated with an increased risk for DYS: older age, white race, PI use and male sex. Diagnoses of hypertension, hepatitis C virus infection, depression or opportunistic infections were all negatively associated with a DYS diagnosis. When controlled for length of follow up, patients with DYS (and no CV-related events) incurred greater median and mean total average costs than patients without DYS or CV-related events. For patients with more than 2 years of follow up, these total cost differences were statistically significant (P<0.05). CONCLUSIONS: These findings indicate that DYS is common among patients with HIV infection and is associated with increased use of medical resources.

Estimating activity limitation in the noninstitutionalized population: a method for small areas.

OBJECTIVES: Although reliable direct state and local estimates of the activity-limited population are frequently unavailable, regression-adjusted synthetic estimates can be made. Such estimates use multivariate methods to model activity limitation at the national level and then apply model-predicted probabilities to corresponding community-specific demographic data. METHODS: Using the 1989 National Health Interview Survey and the 1991 Area Resource File System, this study produced log-linear regression models that included person-level demographic and county-level contextual variables as predictors of activity limitation. Model-predicted rates were then multiplied by corresponding intercensal population data to generate state and local synthetic estimates of activity limitation. RESULTS: Rates of activity limitation generally were found to increase with age and as the socioeconomic conditions of the county in which an individual resided worsened. Race and sex also tended to be statistically significant predictors of activity limitation. CONCLUSIONS: Activity limitation can be effectively modeled by age, sex, race, and community socioeconomic status. Synthetic estimates such as these are relatively simple to generate and can be useful for small-area planning in the absence of direct local estimates.

Anticoagulation clinics and patient self-testing for patients on chronic warfarin therapy: A cost-effectiveness analysis.

This study was intended to evaluate the cost-effectiveness of anticoagulation clinic care and self-testing for the management of patients on chronic warfarin therapy. Using a 5-year Markov model, we evaluated the health and economic outcomes associated with each of three different anticoagulation management approaches: (1) usual care, (2) anticoagulation clinic testing with a capillary monitor, and (3) patient self-testing with a capillary monitor. Data available in the published literature and data from a large health system were used to develop model assumptions. Model results indicate that over a 5-year period, compared with usual care, anticoagulation clinic testing results in a total of 1.7 fewer thromboembolic events and 2.0 less hemorrhagic events per 100 patients. Another 4.0 thromboembolic events and 0.8 hemorrhagic events are avoided with patient self-testing compared with anticoagulation clinic testing. In addition to the health advantages of these strategies, both also have cost advantages. When the costs incurred by provider organizations and patients are considered, patient self-testing is the most cost-effective alternative, resulting in an overall cost saving.

The cost-effectiveness of different management strategies for patients on chronic warfarin therapy.

OBJECTIVE: To examine the cost-effectiveness of moving from usual care to more organized management strategies for patients on chronic warfarin therapy. DESIGN: Using information available in the scientific literature, supplemented with data from a large health system and, when necessary, expert opinion, we constructed a 5-year Markov model to evaluate the health and economic outcomes associated with each of three different anticoagulation management approaches: usual care, anticoagulation clinic testing with a capillary monitor, and patient self-testing with a capillary monitor. PATIENTS: Three hypothetical cohorts of patients beginning long-term warfarin therapy were used to generate model results. MAIN RESULTS: Model results indicated that moving from usual care to anticoagulation clinic testing would result in a total of 1.7 thromboembolic events and 2.0 hemorrhagic events avoided per 100 patients over 5 years. Another 4.0 thromboembolic events and 0.8 hemorrhagic events would be avoided by moving to patient self-testing. When direct medical care costs and those incurred by patients and their caregivers in receiving care were considered, patient self-testing was the most cost-effective alternative, resulting in an overall cost saving. CONCLUSIONS: Results illustrate the potential health and economic benefits of organized care management approaches and capillary monitors in the management of patients receiving warfarin therapy.

A Web-based diabetes care management support system.

BACKGROUND: Because of the often asymptomatic nature of diabetes and the long period between sustained hyperglycemia and observable complications, appropriate diabetes care relies on a long-term program of secondary prevention. Yet routine monitoring and screening among patients with diabetes is less than optimal. To support the provision of routine care to patients with diabetes, the Center for Health Services Research, Henry Ford Health System (Detroit), developed a Web-based Diabetes Care Management Support System (DCMSS). A nonrandomized, longitudinal study was conducted (January 1, 1998-October 31, 1999) with 13,325 health maintenance organization patients with diabetes who were aligned to 190 primary care providers practicing in 31 primary care clinics. RESULTS: Three DCMSS features--clinical practice guidelines, patient registries, and performance reports--were made available via a corporate intranet within an existing electronic medical record. The effect of DCMSS usage frequency was evaluated on the likelihood of a patient's receipt of glycated hemoglobin testing, lipid profile testing, and retinal examinations. Logistic regression models controlling for patient sociodemographic and clinical characteristics, and the testing history of the patient, the primary care physician, and the primary care clinic, were fit using generalized estimating equation methods. The more often a physician used DCMSS, the more likely his or her patients were to receive lipid profile testing (OR [odds ratio] = 1.01, 95% CI [confidence interval] = 1.01-1.02). Compared with patients of physicians who never used the system, patients of physicians who initiated 12 sessions were an estimated 19% more likely (95% CI = 7%-33%) to receive lipid profile testing. The analyses also suggested that the likelihood of a patient receiving a retinal exam was associated with system usage (OR = 1.01, 95% CI = 1.01-1.01). No relationship was found between system use and glycated hemoglobin testing. CONCLUSIONS: Computerized systems of clinical practice guidelines, patient registries, and performance feedback may help improve the rate of routine testing among patients with diabetes.

Provider type and the receipt of general and diabetes-related preventive health services among patients with diabetes.

OBJECTIVE: Using a measure of provider type that includes "shared care" to determine the contribution of provider type on receipt of general and diabetes-related preventive health services. METHODS: Automated clinical and administrative data were used to identify adult patients with type 1 and 2 diabetes receiving care from a multispecialty, salaried group practice and enrolled in a large health maintenance organization between 3/97 and 2/98 (n = 10,991). Logistic regression models were fit using generalized estimating equation approaches to evaluate the contribution of provider type on service receipt. MEASURES: Preventive service receipt included receipt of glycated hemoglobin and lipid testing, retinal examinations, pneumococcal vaccines, Papanicolaou (Pap) smears, and mammograms. Multivariable analyses adjusted for age, sex, race, marital status, household income, diabetes-related comorbidities and complications, prescription drug use, laboratory testing results, and frequency of medical care contact. RESULTS: Patients seeing an endocrinologist and primary care physician (PCP) were more likely than those seeing endocrinologists alone to receive glycated hemoglobin testing (OR, 1.42), lipid testing (OR, 1.72), mammograms (OR, 2.12), and Pap smears (OR, 2.36), and more likely than those seeing PCPs alone to receive glycated hemoglobin testing (OR, 1.79), lipid testing (OR, 1.54), retinal examinations (OR, 1.33), and mammograms (OR, 1.43). Compared with patients seeing PCPs only, patient's seeing endocrinologists only were more likely to receive retinal examinations (OR, 1.37) and less likely to receive Pap smears (OR, 0.46). CONCLUSIONS: Care delivered by no one single provider type is associated with greater receipt of all recommended services. Instead, patients seeing both an endocrinologist and a PCP are most likely to receive recommended services.

Prevalence and impact of migraine and probable migraine in a health plan.

BACKGROUND: A large number of headache sufferers with features of migraine fail to meet criteria for strict migraine (SM; migraine with or without aura) but do meet criteria for probable migraine (PM). OBJECTIVES: To estimate the prevalence of PM, to compare the epidemiologic profiles of SM and PM, and to assess the disability and impact on the health-related quality of life (HRQoL) of these patients. METHODS: Computer-assisted telephone interviews in a sample recruited from a mixed model health maintenance organization were used. SM, PM, and control subjects were identified. Also assessed were demographic features, disability, HRQoL, and depression. RESULTS: The 1-year prevalence for SM was 14.7% (19.2% in women and 6.6% in men); for PM, it was 14.6% (15.9% in women, 12.6% in men). Most subjects with PM (82%) did not meet the associated symptom criteria for migraine. HRQoL was reduced in the PM, SM, and all migraine (AM; SM and PM pooled together) groups compared with controls. The proportion of subjects with high disability was elevated in PM (13%), SM (31%), and AM (22%) groups vs controls (3.7%; p < 0.0001). CONCLUSIONS: Within a health plan, probable migraine is a prevalent form of migraine, with symptom and epidemiologic profiles that overlap with strict migraine. Although strict migraine prevalence was consistent with previous studies, a probable migraine prevalence higher than previously reported was found, perhaps reflecting a difference between health plan and population samples.

Health service use by African Americans and Caucasians with asthma in a managed care setting.

Managed care plan members provide a population for analysis that minimizes the financial barriers to routine medical care that have been linked to high rates of asthma-related hospitalization, emergency care, and mortality among urban African Americans. We examined patterns of asthma care among 464 African American (AA) and 1,609 Caucasian (C) asthma patients, age 15 to 45 yr, in a southeast Michigan managed care system during 1993. Compared with C, AA had fewer visits to asthma specialists (0.32 versus 0.50 visits/yr, p = 0.002), and filled fewer prescriptions for inhaled steroids (1.44 versus 1.74 Rx/yr, p = 0.038), while being more likely to visit the emergency department with asthma (0.71 versus 0.28 visits/yr, p < 0. 001), to be hospitalized with asthma (0.08 versus 0.03 admissions/yr, p = 0.002), or to have filled prescriptions for oral steroids (0.91 versus 0.59 Rx/yr, p < 0.001). AA were equally likely to have visited a primary care physician for asthma (0.95 versus 0.93 visits/yr, p = 0.81). Similar physician visit profiles and discrepancies in the use of oral steroids persisted when analyzing exclusively low socioeconomic status subgroups. These results suggest that ethnic differences in patterns of asthma-related health care persist within managed care settings and are only partially due to financial barriers.