Rates and costs of invasive pneumococcal disease and pneumonia in persons with underlying medical conditions.

BACKGROUND: The presence of certain underlying medical conditions is known to increase the risk of pneumococcal disease in persons of all ages and across a wide spectrum of conditions, as demonstrated in two recent evaluations. Corresponding estimates of attributable economic costs have not been well characterized. We thus undertook a retrospective evaluation to estimate rates and costs of pneumococcal disease among children and adults with and without underlying medical conditions in the United States. METHODS: Data were obtained from three independent healthcare claims repositories. The study population included all persons enrolled in participating health plans during 2007-2010, and was stratified into subgroups based on age and risk profile: healthy; at-risk, due to selected comorbid conditions; and high-risk, due to selected immunocompromising conditions. At-risk and high-risk conditions, as well as episodes of invasive pneumococcal disease (IPD) and all-cause pneumonia (PNE), were identified via diagnosis, procedure, and drug codes. Rates and healthcare costs of IPD and PNE (2010US$) among at-risk and high-risk persons were compared with those from age-stratified healthy counterparts using incidence rate ratios (IRR) and cost ratios. RESULTS: Rates of IPD and PNE were consistently higher among at-risk persons (IRR = 4.1 [95 % CI 3.9-4.3] and 4.5 [4.49-4.53]) and high-risk persons (IRR = 10.3 [9.7-11.0] and 8.2 [8.2-8.3]) of all ages versus their healthy counterparts. Rates were notably high for at-risk persons with ≥2 conditions (IRR = 9.0 [8.4-9.7] and 10.3 [10.3-10.4]), as well as those with asthma (IRR = 3.4 [3.0-3.8] and 4.5 [4.47-4.53]) or diabetes (IRR = 4.3 [4.0-4.6] and 4.7 [4.6-4.7]). Healthcare costs totaled $21.7 million per 100,000 at-risk person-years and $58.5 million per 100,000 high-risk person-years, which were 8.7 [8.5-8.8] and 23.4 [22.9-23.8] times higher than corresponding costs for healthy persons. CONCLUSIONS: Rates and costs of IPD and PNE are substantially higher among persons with certain chronic and immunocompromising conditions versus those without any such conditions. Rates and costs for persons with asthma and diabetes were especially increased, and rates and costs for individuals with ≥2 at-risk conditions approached those among persons with high-risk conditions.

Rates of pneumonia among children and adults with chronic medical conditions in Germany.

BACKGROUND: The objective of this study is to evaluate rates of all-cause pneumonia among "at-risk" and "high-risk" children and adults in Germany-in comparison with age-stratified healthy counterparts-during the period following the 2006 recommendation for universal immunization of infants with pneumococcal conjugate vaccine. METHODS: Retrospective cohort design and healthcare claims information for 3.4 M persons in Germany (2009-2012) were employed. Study population was stratified by age and risk profile (healthy, "at-risk" [with chronic medical conditions], and "high-risk" [immunocompromised]). At-risk and high-risk conditions, as well as episodes of all-cause pneumonia, were identified via diagnosis, procedure, and drug codes. RESULTS AND DISCUSSION: Rates of all-cause pneumonia were 1.7 (95 % CI 1.7-1.8) to 2.5 (2.4-2.5) times higher among children and adults with at-risk conditions versus healthy counterparts, and 1.8 (1.8-1.9) to 4.1 (4.0-4.2) times higher among children and adults with high-risk conditions. Rates of all-cause pneumonia among at-risk persons increased in a graded and monotonic fashion with increasing numbers of conditions (i.e., risk stacking). CONCLUSIONS: An increased risk for all-cause pneumonia in German children and adults with a spectrum of medical conditions persists in the era of widespread pneumococcal vaccination, and pneumonia risk in persons with ≥2 at-risk conditions is comparable or higher than those with high-risk conditions.

Despite High Cost, Improved Pneumococcal Vaccine Expected To Return 10-Year Net Savings Of $12 Billion.

In 2010 the US Advisory Committee on Immunization Practices recommended that the seven-valent pneumococcal conjugate vaccine (PCV7) be replaced by the thirteen-valent version (PCV13), which provides protection against six additional serotypes of the bacterium Streptococcus pneumoniae. The higher price of PCV13, compared to PCV7, may be a concern for funding agencies and payers, as has been the case with other new vaccines. This study estimated the budgetary impact on both public and private US insurance payers of the routine use of PCV13 instead of PCV7 from 2010 to 2019. Implementing the PCV13 vaccine is projected to cost public and private payers $3.5 billion and $2.6 billion, respectively, more than PCV7. However, PCV13 is expected to provide net cost savings of $6.1 billion and $4.2 billion, respectively, to those payers during the ten-year period by preventing pneumococcal disease and its associated costs. An additional $1.7 billion in cost savings would be realized for uninsured patients, whose costs ultimately fall on those payers. Despite its higher price, compared to PCV7, this new vaccine is expected to provide payers with substantial net budgetary savings.

Rethinking risk for pneumococcal disease in adults: the role of risk stacking.

Using data from 3 private healthcare claims repositories, we evaluated the incidence of pneumococcal disease among adults with US Advisory Committee on Immunization Practices (ACIP) defined at-risk conditions or rheumatoid arthritis, lupus, Crohn's disease, and neuromuscular disorder/seizures and those with traditional high-risk conditions. We observed that adults with ≥2 concurrent comorbid conditions had pneumococcal disease incidence rates that were as high as or higher than rates observed in those with traditional high-risk conditions.

Risk of pneumococcal disease in children with chronic medical conditions in the era of pneumococcal conjugate vaccine.

BACKGROUND: In the current era of universal immunization of young children with pneumococcal conjugate vaccine, it is unclear whether the high risk ratios for pneumococcal disease previously attributed to specified chronic conditions have persisted. In addition, further analysis of pneumococcal disease risk may clarify whether certain chronic conditions that currently are not specified as significantly increasing the risk of pneumococcal disease should be so considered. METHODS: We conducted a retrospective cohort analysis utilizing healthcare claims data from the period 2007-2010 to compare rates of pneumococcal disease among children <5 and 5-17 years of age with high-risk and at-risk conditions to rates among children without these conditions in the same age group. Risk profiles and manifestations of pneumococcal infection were ascertained from diagnosis, procedure, and drug codes. RESULTS: Among at-risk children, rate ratios for invasive pneumococcal disease (vs children without at-risk/high-risk conditions) were 1.8 (95% confidence interval [CI], 1.4-2.3) in children <5 years of age and 3.3 (95% CI, 2.4-4.4) in children 5-17 years of age. Corresponding rate ratios for high-risk children were 11.2 (95% CI, 7.0-17.9) and 40.1 (95% CI, 28.8-56.0). Rate ratios increased in asthmatic children with increasing disease severity and in all at-risk children by the number of concurrent at-risk conditions. Rate ratios for pneumococcal pneumonia and all-cause pneumonia demonstrated similar patterns. CONCLUSIONS: Children with high-risk and at-risk conditions continue to demonstrate an increased burden of pneumococcal disease. Pneumococcal disease rates are high among asthmatic children with moderate and severe disease and children with multiple at-risk conditions.

Rates of pneumococcal disease in adults with chronic medical conditions.

BACKGROUND: Although it is widely accepted that adults with immunocompromising conditions are at greatly increased risk of pneumococcal infection, the extent of risk among immunocompetent adults with chronic medical conditions is less certain, particularly in the current era of universal vaccination of children with pneumococcal conjugate vaccines. METHODS: We conducted a retrospective cohort study using data from 3 healthcare claims repositories (2006-2010) to compare rates of pneumococcal disease in immunocompetent adults with chronic medical conditions ("at-risk") and immunocompromised adults ("high-risk"), with rates in adults without these conditions ("healthy"). Risk profiles and episodes of pneumococcal disease-all-cause pneumonia, pneumococcal pneumonia, and invasive pneumococcal disease (IPD)-were ascertained from diagnosis, procedure, and drug codes. RESULTS: Rates of all-cause pneumonia among at-risk persons aged 18-49 years, 50-64 years, and ≥65 years were 3.2 (95% confidence interval [CI], 3.1-3.2), 3.1 (95% CI, 3.1-3.1), and 3.0 (95% CI, 3.0-3.0) times the rates in age-matched healthy counterparts, respectively. We identified rheumatoid arthritis, systemic lupus erythematosus, Crohn's disease, and neuromuscular or seizure disorders as additional at-risk conditions for pneumococcal disease. Among persons with at-risk conditions, the rate of all-cause pneumonia substantially increased with the accumulation of concurrent at-risk conditions (risk stacking): among persons 18-49 years, rate ratios increased from 2.5 (95% CI, 2.5-2.5) in those with 1 at-risk condition to 6.2 (95% CI, 6.1-6.3) in those with 2 conditions, and to 15.6 (95% CI, 15.3-16.0) in those with ≥3 conditions. Findings for pneumococcal pneumonia and IPD were similar. CONCLUSIONS: Despite widespread use of pneumococcal conjugate vaccines, rates of pneumonia and IPD remain disproportionately high in adults with at-risk conditions, including those with conditions not currently included in the Advisory Committee on Immunization Practices' guidelines for prevention and those with multiple at-risk conditions.

Impact of 13-valent pneumococcal conjugate vaccine (PCV13) in a pandemic similar to the 2009 H1N1 in the United States.

BACKGROUND: High rates of bacterial coinfection in autopsy data from the 2009 H1N1 influenza ("flu") pandemic suggest synergies between flu and pneumococcal disease (PD) during pandemic conditions, and highlight the importance of interventions like the 13-valent pneumococcal conjugate vaccine (PCV13) that may mitigate the impact of a pandemic. METHODS: We used a decision-analytic model, estimated from published sources, to assess the impact of pediatric vaccination with PCV13 versus the 7-valent vaccine (PCV7) on PD incidence and mortality in a normal flu season (10% flu incidence) and in a pandemic similar to 2009-2010 H1N1 (20% flu incidence, mild virulence, high impact in children). Both direct and indirect (herd) effects against PD were considered. Effectiveness of PCV13 was extrapolated from observed PCV7 data, using assumptions of serotype prevalence and PCV13 protection against the 6 serotypes not in PCV7. To simulate 2009-2010 H1N1, autopsy data were used to estimate the overall proportion of flu deaths with bacterial coinfections. By assuming that increased risk of death during the pandemic occurred among those with comorbidity (using obesity as proxy) and bacterial coinfections primarily due to S. pneumoniae or S. aureus, we estimated the proportion co-infected among all (fatal and non-fatal) flu cases (7.6% co-infected with any organism; 2.2% with S. pneumoniae). PD incidence, mortality, and total healthcare costs were evaluated over a 1-year horizon. RESULTS: In a normal flu season, compared to PCV7, PCV13 is expected to prevent an additional 13,400 invasive PD (IPD) cases, 399,000 pneumonia cases, and 2,900 deaths, leading to cost savings of $472 M. In a pandemic similar to 2009-2010 H1N1, PCV13 would prevent 22,800 IPD cases, 872,000 pneumonia cases, and 3,700 deaths, resulting in cost savings of $1.0 B compared to PCV7. CONCLUSIONS: In a flu pandemic similar to the 2009-2010 H1N1, protection against the 6 additional serotypes in PCV13 would likely be effective in preventing pandemic-related PD cases, mortality, and associated costs.

Cost-effectiveness of a 10- versus 13-valent pneumococcal conjugate vaccine in Denmark and Sweden.

BACKGROUND: The introduction of a 7-valent pneumococcal polysaccharide-protein conjugate vaccine (PCV7) had profound public health effects across the globe. PCV7 vaccination in a national immunization program is generally considered cost-effective and potentially cost-saving. Two new PCVs have been launched, a 10-valent pneumococcal conjugate vaccine (PCV10) and a 13-valent pneumococcal conjugate vaccine (PCV13). OBJECTIVE: This article examines the public health and economic effects of pediatric national immunization programs of PCV10 and PCV13 in Denmark and Sweden. METHODS: A previously published decision-analytic model was used to estimate the impact of PCV10 and PCV13 on reducing cases of invasive pneumococcal disease (IPD), pneumonia (PNE), and acute otitis media (AOM) by using country-specific incidence, serotype coverage, disease sequelae, mortality, vaccine effectiveness, indirect effects, costs, and utilities. Direct effects for PCV13- and PCV10-covered serotypes were assumed similar to PCV7. PCV13 was assumed to confer an indirect effect, similar to PCV7, whereas PCV10 was not. Assumptions were tested in sensitivity analyses. RESULTS: PCV13 is expected to save 280.7 million DKK (Danish kroner) in Denmark and 288.2 million SEK (Swedish kronor) in Sweden in direct costs compared with a vaccination program with PCV10. In both Denmark and Sweden, the results of this study indicate that, compared with PCV10, PCV13 will have a greater impact on disease in life-years gained (LYG), quality-adjusted life-years (QALYs) gained, IPD cases avoided, PNE cases avoided, AOM cases avoided, and in deaths avoided. For Denmark PCV13, it was estimated to result in 10,051 LYG; 9063 QALYs gained; 237 additional IPD cases avoided; 12,094 additional PNE cases avoided; 958 additional cases of AOM avoided; and 882 additional deaths avoided. For Sweden PCV13, it was estimated to result in 4245 LYG; 3953 QALYs gained; 379 additional IPD cases avoided; 8210 additional PNE cases avoided; 1459 additional cases of AOM avoided; and 378 additional deaths avoided. In all sensitivity analyses, PCV13 was less costly and more effective compared with PCV10. CONCLUSIONS: In this analysis, a national immunization program with PCV13 was found to be good value for money and estimated to prevent additional cases of disease among children and nonvaccinated individuals and save additional costs due to treatment of pneumococcal disease, when compared with PCV10 in Denmark and Sweden.

Cost-effectiveness models of pneumococcal conjugate vaccines: variability and impact of modeling assumptions.

Currently, 13-valent pneumococcal conjugate vaccine (PCV); and ten-valent PCV vaccine are marketed. Neither vaccine obtained regulatory approval based on efficacy trials, but instead were approved based on a surrogate end point: immunogenicity data measuring effective antibody levels. Therefore, direct measures of efficacy were unavailable at the time economic analyses were conducted. The authors systematically reviewed cost-effectiveness studies of ten-valent PCV and 13-valent PCV from the literature to analyze the methodologies and compare the assumptions made about vaccine effectiveness. The following three inputs were found the most variant across analyses: efficacy against acute otitis media; inclusion of indirect effects; and cross protection. These assumptions are discussed with regard to the validity of supporting data and implications on decision-making.

Modeling the impact of the 13-valent pneumococcal conjugate vaccine serotype catch-up program using United States claims data.

BACKGROUND: Analysis of US claims data from April 2010 to June 2011 estimated that 39% of the 13-valent pneumococcal conjugate vaccine (PCV13) catch-up eligible cohort would ever receive the catch-up vaccination; a previous analysis assumed 87%. METHODS: This updated figure was applied to a previously published 10-year Markov model while holding all other inputs constant. RESULTS: Our model estimated that the catch-up program as currently implemented is estimated to prevent an additional 1.7 million cases of disease in children aged ≤ 59 months over a 10-year period, compared with routine PCV13 vaccination with no catch-up program. CONCLUSIONS: Because 39% catch-up uptake is less than the level of completion of the 4-dose primary PCV13 series, vaccine-preventable cases of pneumococcal disease and related deaths could be decreased further with additional uptake of catch-up vaccination in the catch-up eligible cohort.

Cost-effectiveness of 13-valent pneumococcal conjugate vaccine: Germany, Greece, and The Netherlands.

BACKGROUND: Seven-valent pneumococcal conjugate vaccine (PCV7) had profound public-health impacts and is considered cost-effective and potentially cost saving. Two new PCVs have been launched, a 10-valent vaccine (PCV10) and a 13-valent vaccine (PCV13). We examined public-health and economic impacts of PCV pediatric national immunization programs (NIPs) in Germany, Greece, and the Netherlands. METHODS: A decision-analytic model was developed to estimate the impact of PCV13, PCV7, and 10-valent pneumococcal conjugate vaccine (PCV10) on invasive pneumococcal disease (IPD), pneumonia (PNE), and acute otitis media (AOM). Using epidemiological data, we calculated the cases of IPD, PNE, and AOM, using country-specific incidence, serotype coverage, disease sequelae, mortality, vaccine effectiveness, indirect effects, costs, and utilities. Direct effects for PCV13- and PCV10-covered serotypes were assumed similar to PCV7. PCV13 was assumed to confer an indirect effect, while PCV10 was not. Assumptions were tested in sensitivity analyses. RESULTS: In a NIP, PCV13 was estimated to eliminate 31.7%, 46.4%, and 33.8% of IPD in Germany, Greece, and the Netherlands, respectively. Compared with PCV7 and PCV10, PCV13 was found to be cost-effective or cost saving in all cases when PCV13 indirect effects were included. CONCLUSIONS: Pediatric NIPs with PCV13 in Europe are expected to have dramatic public-health impacts and be cost-effective or cost saving.

Public health and economic impact of the 13-valent pneumococcal conjugate vaccine (PCV13) in the United States.

The 7-valent pneumococcal conjugate vaccine (PCV7) has dramatically decreased pneumococcal disease incidence, and the 13-valent vaccine (PCV13) protects against 6 additional Streptococcus pneumoniae serotypes. A decision-analytic model was constructed to evaluate the impact of infant vaccination with PCV13 versus PCV7 on pneumococcal disease incidence and mortality as well as the incremental benefit of a serotype catch-up program. PCV13 effectiveness was extrapolated from observed PCV7 data, using assumptions regarding serotype prevalence and PCV13 protection against additional serotypes. The model predicts that PCV13 is more effective and cost saving compared with PCV7, preventing 106,000 invasive pneumococcal disease (IPD) cases and 2.9 million pneumonia cases, and saving $11.6 billion over a 10-year period. The serotype catch-up program would prevent an additional 12,600 IPD cases and 404,000 pneumonia cases, and save an additional $737 million compared with no catch-up program.

Public health and economic impact of vaccination with 7-valent pneumococcal vaccine (PCV7) in the context of the annual influenza epidemic and a severe influenza pandemic.

BACKGROUND: Influenza pandemic outbreaks occurred in the US in 1918, 1957, and 1968. Historical evidence suggests that the majority of influenza-related deaths during the 1918 US pandemic were attributable to bacterial pneumococcal infections. The 2009 novel influenza A (H1N1) outbreak highlights the importance of interventions that may mitigate the impact of a pandemic. METHODS: A decision-analytic model was constructed to evaluate the impact of 7-valent pneumococcal conjugate vaccine (PCV7) on pneumococcal disease incidence and mortality during a typical influenza season (13/100) and a severe influenza pandemic (30/100). Outcomes were compared for current PCV7 vaccination practices vs. no vaccination. The model was estimated using published sources and includes indirect (herd) protection of non-vaccinated persons. RESULTS: The model predicts that PCV7 vaccination in the US is cost saving for a normal influenza season, reducing pneumococcal-related costs by $1.6 billion. In a severe influenza pandemic, vaccination would save $7.3 billion in costs and prevent 512,000 cases of IPD, 719,000 cases of pneumonia, 62,000 IPD deaths, and 47,000 pneumonia deaths; 84% of deaths are prevented due to indirect (herd) protection in the unvaccinated. CONCLUSIONS: PCV7 vaccination is highly effective and cost saving in both normal and severe pandemic influenza seasons. Current infant vaccination practices may prevent >1 million pneumococcal-related deaths in a severe influenza pandemic, primarily due to herd protection.

Cost-effectiveness of pneumococcal conjugate vaccine: an update after 7 years of use in the United States.

Seven-valent pneumococcal conjugate vaccine (PCV7) has been in routine use in the United States since 2000 and data have indicated direct and indirect effects of the vaccine. We simulated the effects of PCV7 on children vaccinated during 2000-2006, incorporating direct and indirect effects on incidence of invasive pneumococcal disease (IPD), hospitalized pneumonia and otitis media. Before accounting for indirect effects, PCV7 cost $201,000 per life-year saved. After incorporating indirect effects on IPD, cost per life-year saved was $10,400. The presence of modest additional indirect effects against hospitalized pneumonia and otitis media in children may have resulted in overall cost savings.

Transmission-dynamic model to capture the indirect effects of infant vaccination with Prevnar (7-valent pneumococcal conjugate vaccine (PCV7)) in older populations.

We developed an age-structured, transmission-dynamic, mathematical model to quantify the direct and indirect benefits of infant PCV7 vaccination. The model simulates the acquisition of asymptomatic carriage of Streptococcus pneumoniae and the development of fatal and non-fatal invasive pneumococcal disease (IPD) among vaccinated and unvaccinated individuals aged <2, 2-4, 5-17, 18-49, 50-64, and >or=65 years old. The model was parameterized using published US surveillance data, supplemented with data from published literature. The model predicts the observed incidence of IPD with good agreement and may be used to predict the impact of various vaccination strategies in the US or other populations yet to introduce PCV7.

The impact of indirect (herd) protection on the cost-effectiveness of pneumococcal conjugate vaccine.

BACKGROUND: The heptavalent pneumococcal polysaccharide-protein conjugate vaccine (PCV7) confers protection against invasive pneumococcal disease (IPD) caused by serotypes that are responsible for substantial morbidity and mortality throughout the world. In 2000, the 7 serotypes covered by PCV7 accounted for 80% to 90% of serotypes isolated from the blood or cerebrospinal fluid of children aged <6 years in the United States. A previous review of the literature spanning the years 1998 to 2005 pertaining to the incidence of IPD among nonimmunized individuals in countries with universal PCV7 immunization suggested an indirect protective effect (herd protection, or community immunity) after widespread vaccination. Consideration of indirect protection against IPD may enhance cost-benefit evaluations of vaccination programs. OBJECTIVE: The objective of this analysis was to review the literature on cost-effectiveness analyses of PCV7 vaccination to determine whether inclusion of the indirect effect in decision-analysis models substantially affects the cost-effectiveness findings in favor of vaccination. METHODS: A literature review of cost-effectiveness analyses of PCV7 vaccination was conducted using the DIMDI (Deutschen Institut fur Medizinische Dokumentation und Information) superbase, which comprises 12 databases, to identify articles published between January 2000 and October 2006 using the search terms 7-valent pneumococcal conjugate vaccine AND herd immunity/herd effect, and 7-valent pneumococcal conjugate vaccine AND cost-effectiveness, cost-utility, or cost-benefit analyses. Monetary values were converted to euros and inflated to 2006 values, and events avoided were converted to rates per 100,000 vaccinated to allow comparison across studies. The sensitivity analyses from the models that included indirect effects were examined. RESULTS: There was wide variability in the health-economic results of the 16 studies that met the inclusion criteria. In studies that did not include indirect effects, the adjusted cost per life-year gained ranged from cost saving to euro140,723 from the societal perspective and from euro56,724 to euro324,218 from the payer perspective. In the 4 studies that included indirect effects, a significant and consistent improvement was seen in the health-economic results in favor of vaccination with PCV7. No trends in variability across time or geographic region were observed. CONCLUSIONS: Indirect effects had a significant effect on cost-effectiveness, as seen in the sensitivity analyses. Future models should include indirect effects in evaluating the cost-effectiveness of PCV7.

Influence of medication treatment patterns on resource use for patients hospitalized for schizophrenia.

PURPOSE: The influence of medication treatment patterns on resource use for patients hospitalized for schizophrenia was studied. METHODS: Patients hospitalized with a primary diagnosis of schizophrenia or schizo-affective disorder discharged between October 1, 2003, and September 30, 2004, were identified from a large, multihospital database. The duration of dosage adjustment was defined as the period between first and last days of dosage change. Ordinary least-squares regression was used to examine the relationships between labeled dosage-escalation durations, actual durations of dosage adjustment, and length of stay. RESULTS: The study sample consisted of 21,950 hospitalized schizophrenia patients, representing 30,873 hospitalizations from 157 hospitals. The majority of patients were 18-44 years old (56.3%), covered by Medicare (46.6%), and admitted through the emergency room (55.5%). The average length of hospital stay was 10 days, and 30% of patients were readmitted for a related reason within 90 days. The labeled dosage-escalation duration was not correlated with the actual duration of dosage adjustment (r = 0.05, p < 0.0001) or with longer hospital stays (r = -0.03, p < 0.0001). Drug-related factors affecting length of stay included medication changes (p < 0.0001), dose changes (p < 0.0001), use of short-acting intramuscular antipsychotics ( p < 0.0001), and medications to manage extrapyramidal symptoms (p < 0.0001). CONCLUSION: Analysis of information about patients hospitalized for schizophrenia revealed that antipsychotic medication changes, prolonged dosage escalation, and initial use of short-acting intramuscular antipsychotics were significantly associated with a greater than average length of stay. Longer labeled dosage-escalation durations were not associated with longer hospital stays.

US prevalence of hyperhidrosis and impact on individuals with axillary hyperhidrosis: results from a national survey.

BACKGROUND: The current epidemiologic data on hyperhidrosis are scarce and insufficient to provide precise prevalence or impact estimates. OBJECTIVE: We sought to estimate the prevalence of hyperhidrosis in the US population and assess the impact of sweating on those affected by axillary hyperhidrosis. METHODS: A nationally representative sample of 150,000 households was screened by mailed survey for hyperhidrosis and projected to the US population based on US census data. Ascertainment of hyperhidrosis was based on a question that asked whether participants experienced excessive or abnormal/unusual sweating. RESULTS: The prevalence of hyperhidrosis in the survey sample was 2.9% (6800 individuals). The projected prevalence of hyperhidrosis in the United States is 2.8% (7.8 million individuals), and 50.8% of this population (4.0 million individuals) reported that they have axillary hyperhidrosis (1.4% of the US population). Only 38% had discussed their sweating with a health care professional. Approximately one third of individuals with axillary hyperhidrosis (0.5% of the US population or 1.3 million individuals) reported that their sweating is barely tolerable and frequently interferes, or is intolerable and always interferes, with daily activities. CONCLUSION: Hyperhidrosis affects a much larger proportion of the US population than previously reported. More than half of these individuals have axillary hyperhidrosis, in which sweating can result in occupational, emotional, psychological, social, and physical impairment.

Trends in glaucoma surgery before and after the introduction of new topical glaucoma pharmacotherapies.

OBJECTIVE: Recent advances in pharmacotherapy that have improved the ability to effect sustained reductions in intraocular pressure may delay or obviate the need for surgery for open-angle glaucoma. This analysis explored this possibility by evaluating the frequency of surgeries for open-angle glaucoma in the US Medicare population before and after the 1996 introduction of latanoprost, a topical prostaglandin analogue with potent ocular antihypertensive efficacy and a better safety profile than older topical glaucoma medications. METHODS: Data from the Medicare 5% Standard Analytical File were used to develop national estimates of the frequency of glaucoma surgeries in the US yearly from 1994 through 1999. RESULTS: While the number of US Medicare patients with a diagnosis of glaucoma remained constant from 1994 through 1999, the number of inpatient and outpatient glaucoma surgeries declined with a particularly sharp drop between 1996 and 1997. In 1999 relative to 1994, the number of annual glaucoma surgeries among unique patients with a diagnosis of glaucoma was reduced by 72% for inpatient procedures and 42% for outpatient procedures. CONCLUSIONS: The number of glaucoma surgeries among US Medicare patients markedly decreased from 1994 to 1999, during which time the prevalence of glaucoma remained stable in this population. The decrease in surgeries coincided with the introduction of improved topical pharmacotherapies for the management of glaucoma. Although the ability to infer a causal relationship between introduction of new pharmacotherapy and the decrease in surgeries is limited, the consistency of these data with those of several other studies renders the findings compelling.