Recent trends in lung cancer and its association with COPD: an analysis using the UK GP Research Database.

BACKGROUND: The association between lung cancer and COPD has not been investigated in the primary care setting. METHOD: We determined the recent trends of lung cancer in COPD patients in the UK during the period 1991-2004, by investigating the population aged 45 and over in the General Practice Research Database. RESULTS: The annual-incidence rates of lung cancer per 10,000 person-years were at least four-fold higher in patients with prior COPD (increasing from 45 to 64 in men; 29 to 48 in women) compared with the general population (from 10 to 15 in men; 5 to 10 in women). These lung cancer trends had significant annual increases that were similar in men (5%) and in women (5.5%) with prior COPD; in contrast, the annual increases of lung cancer incidence rates in the general population differed by gender, being 4% in men but double in women (8%). The three-year survival for lung cancer patients among those with prior COPD was almost half that of the general population (15% versus 26%; p<0.01) and the highest mortality was observed in men aged 45-64 (83.79 per 100 person-years; 95% CI: 69.66-97.92). CONCLUSION: These results support the association of COPD and lung cancer observed in other settings.

Patterns of comorbidities in newly diagnosed COPD and asthma in primary care.

STUDY OBJECTIVES: There is increasing interest in the frequency and nature of comorbidities in patients with obstructive lung disease: COPD and asthma. We aimed to quantify baseline rates of comorbidities in COPD and asthma patients and to compare the risks to the general population. DESIGN, SETTING, AND PARTICIPANTS: Within the UK General Practice Research Database, we compared incident patients with COPD (n = 2,699) and asthma (n = 7,931) physician diagnosed in 1998 with age, gender, time, and practice-matched cohorts. Rates were calculated and relative risks (RRs) were estimated for comorbidities in major organ systems and selected medical events of a priori interest. MEASUREMENTS AND RESULTS: In both COPD and asthma, the total sum of diagnoses related to major organ systems was higher than in their matched population controls. Among incident COPD patients, a frequency > 1% within the first year after diagnosis was observed for angina, cataracts, bone fractures, osteoporosis, pneumonia, and respiratory infections, the highest being angina with 4.0%. Compared to the non-COPD cohort, COPD patients were at increased risk for pneumonia (relative risk [RR] = 16.0), osteoporosis (RR = 3.1), respiratory infection (RR = 2.2), myocardial infarction (RR = 1.7), angina (RR = 1.7), fractures (RR = 1.6), and glaucoma (RR = 1.3) [all p < 0.05]. Of note, 2.0% of COPD patients had cataracts recorded, but this rate was no different than that of the non-COPD cohort (RR = 0.9). Among incident asthma patients, the occurrence of events was generally lower, likely due to the younger age distribution, except for 4.0% with respiratory infection (RR = 1.84) and 1.7% with fractures (RR = 1.5). Angina prevalence was 0.7% in the asthma cohort and 1.4 times more common than in patients without asthma. CONCLUSION: COPD and asthma are conditions associated with many comorbidities, albeit asthma to a lesser extent than COPD, which had not been systematically reviewed before. Baseline rates of cardiovascular-, bone-, and other smoking-related conditions are high.

Obtaining optimal control in mild asthma: theory and practice.

BACKGROUND: Studies have shown that asthma severity is easily under-estimated and as a result, patients may be under-treated with reduced asthma control. OBJECTIVE: This study, performed in the General Practice Research Database (GPRD), investigates asthma control in patients treated as intermittent asthmatics (short-acting beta agonist (SABA) alone), or persistent asthmatics (additional inhaled cortico-steroid (ICS), no other medication). METHODS: Patients (0-45 years) diagnosed with asthma between 1 January 1995 and 31 December 2001 taking > or =2 scripts for SABA (SABA only group) or > or =3 scripts for ICS (ICS group) in the first six months following diagnosis were selected. Factors associated with drug prescriptions were assessed. RESULTS: SABA script rates were 3.6 and 5.1 per year in the SABA and ICS group respectively, i.e. >1 dose/day. 10.5% of SABA group and 13.4% of ICS group used oral steroids. Within the SABA group, 37% were stepped up to ICS, the time to first ICS script being significantly associated with prior hospitalization (RR 2.26, CI 1.65-3.10) and atopy (RR 1.47, CI 1.33-1.63). A higher rate of oral steroid use was significantly associated with using ICS, being female, adult and smoking. Smokers and atopic individuals had increased risk of obtaining an earlier script for oral steroid (RR 1.32, CI 1.10-1.59 and RR 1.28, CI 1.10-1.49, respectively). CONCLUSIONS: Asthma control was sub-optimal in a substantial proportion of patients using relatively high doses of SABA, or SABA and ICS from the outset of asthma treatment in general practice. Being female, atopic, a smoker and prior hospitalization were all associated with lack of asthma control and could guide physicians in treatment prescribing.

The proportional Venn diagram of obstructive lung disease: two approximations from the United States and the United Kingdom.

STUDY OBJECTIVES: The nonproportional Venn diagram of obstructive lung disease (OLD) produced for the 1995 American Thoracic Society guidelines has not been quantified. We aim to quantify the proportion of the general population with OLD and the intersections of physician-diagnosed asthma, chronic bronchitis, and emphysema in the United States and the United Kingdom, and to examine the relationship to obstructive spirometry. DESIGN AND PARTICIPANTS: We analyzed data from the US National Health and Nutrition Examination (NHANES) III survey (1988 to 1994) and the UK General Practice Research Database for the year 1998. RESULTS: The areas of intersection among the three OLD conditions produced seven mutually exclusive disease groups. The asthma-only group was the largest proportion of OLD patients, accounting for 50.3% and 79.4% of all OLD patients in the United States and the United Kingdom, respectively, and decreased with increasing age. Overall, 17% and 19% of OLD patients in the United States and in the United Kingdom, respectively, reported more than one OLD condition, and this percentage increased with age. According to the spirometry data from NHANES III, only 37.4% of emphysema-only patients had objective airflow obstruction. The prevalence of airflow obstruction was significantly higher among participants with combinations of emphysema and chronic bronchitis (57.7%), with emphysema and asthma (51.9%), and with all three OLD diseases concomitantly (52.0%). CONCLUSION: Concomitant diagnosis of asthma, chronic bronchitis, or emphysema is common among OLD patients from the general population, particularly in adults aged > or = 50 years.

Association between migraine and asthma: matched case-control study.

BACKGROUND: Earlier studies have suggested a link between asthma and severe headache, and also between migraine and wheezing illness. Recent analysis have also shown an increase of asthma among cases with a prior history of migraine but without a history of hay fever, allergic rhinitis or eczema. AIM: To examine whether there is an association between migraine and asthma in the United Kingdom. DESIGN OF STUDY: Matched case-control study using the General Practice Research Database (GPRD). SETTING: Practices in the United Kingdom providing data on 5,110,619 patients to the GPRD. METHOD: The subjects were the patients with one or more diagnoses of migraine plus treatment for migraine. Each case was matched by general practice, sex, and age, with one control who had never been given a diagnosis of migraine. Case and control groups were compared for prevalence of asthma, chronic obstructive pulmonary disease, respiratory symptoms treated with inhalers or hay fever. Investigations were carried out to determine whether the association between migraine and asthma was stronger among patients with hayfever or those without hayfever, and whether patients with migraine had an increased prescription of other (non-migraine and non-asthma) medications. RESULTS: Among 64 678 case-control pairs, the relative risk of asthma in patients with migraine was 1.59 (95% CI = 1.54 to 1.65) among definite cases, and 0.75 (95% CI = 0.67 to 0.83) among those whose selection as case included beta-blocker prophylaxis. Among definite migraine cases, relative risks of chronic obstructive pulmonary disease, respiratory symptoms, eczema, and hay fever (pollinosis), were all raised (at 1.22, 1.85, 1.55, and 1.67, respectively). The association between migraine and asthma was stronger in patients without a diagnosis of hay fever, than in those with hayfever (relative risk = 1.32 and 1.19, respectively). The relative risk of prescription for a range of non-migraine, non-asthma medications was raised, the exception being anti-diabetic medication. CONCLUSION: This large case-control study provides evidence for an association between migraine and asthma. Frequent attendance at a general practice surgery may confound this association. However, if the association is real, its elucidation may help the understanding of disease mechanisms shared by migraine and asthma.