Susan Wells

Aims: Hypertensive disorders of pregnancy (HDP) are established markers of cardiovascular disease (CVD) risk yet are not routinely incorporated into primary prevention. We aimed to (1) assess how HDP is recorded across primary care and national hospitalization data in New Zealand and (2) estimate the association between a history of HDP and incident CVD over 5 years. Methods and results: This cohort study used linked health records from the ProCare Primary Health Organisation and national datasets. HDP was identified from Read-coded and free-text general practice records and ICD-10-AM hospital data. Two analyses were undertaken: (1) comparison of HDP recording between primary care and hospital discharge data among women aged 18–64 years; and (2) estimation of 5-year incident CVD risk among women aged 30–64 years without prior CVD. Cox proportional hazards models estimated adjusted hazard ratios (aHRs), incorporating the linear predictor from a national primary prevention CVD risk equation. Among 172 328 women aged 18–64 years, a history of HDP was recorded in 4.7% (population-level prevalence), with 91% of this recorded in hospital discharge data only. Over 5 years, 2391 women experienced incident CVD events. A recorded history of HDP was associated with a 72% higher CVD risk (aHR = 1.72, 95% confidence interval: 1.49–1.98). Women with HDP experienced cardiovascular events at younger ages than those without (median 50.2 vs. 57.3 years). Conclusion: HDP is inadequately recorded in primary care in New Zealand. When documented, it identifies women at significantly higher and earlier CVD risk. Improving HDP documentation in primary care may enable earlier and more equitable CVD prevention.

Historically, general practice has been taught in the later years of a medical school programme through short clinical placements, with students observing and participating in consultations. The ap...

Background: Multimorbidity adds complexity to medication management. National guidelines in New Zealand (NZ) recommend dual therapy with blood-pressure- and lipid-lowering agents for most patients at five-year cardiovascular disease (CVD) risk ≥15% (high risk), considered at 5-14% (intermediate risk), and not generally recommended at <5% (low risk). Aim: To examine the association between multimorbidity and dispensing of dual therapy across risk strata. Design and setting: A cohort study among 430,286 patients aged 30-79 years without prior CVD, enrolled in the NZ Primary Health Organisation ProCare in 2014. Method: Multivariable Poisson regression estimated relative risks (RR) for dual therapy across CVD risk groups at cohort entry. Two-year maintenance of dual therapy was then compared by multimorbidity within each risk stratum. Results: Baseline dual therapy receipt was 1.5%, 31% and 40% in low, intermediate and high risk groups respectively. Multimorbidity was associated with greater use of dual therapy across risk groups (low risk: RR 2.90 [95% CI 2.77-3.03]; intermediate risk: RR 1.35 [95% CI 1.32-1.38]; high risk: RR 1.15 [95% CI 1.10-1.22]). Multimorbidity was also associated with higher maintenance in the low (88% vs 84%) and intermediate (90% vs 86%) risk groups (both p<0.001) and was high, irrespective of multimorbidity, in high risk (89% vs 88%; p=0.415). Conclusion: Patients with multimorbidity were more likely than others to be commenced on and maintain CVD prevention. However, while dispensing increased with increasing CVD risk, a large evidence-practice gap in dual therapy remained for those at high CVD risk. Keywords: General practice; Multimorbidity; Cardiovascular preventive medication

Background/Objective: Migraine is the second most disabling condition worldwide affecting over one billion people. We aimed to investigate the frequency of recorded migraine utilising general practice and hospital admission data, comparing this with population-based prevalence estimates for Aotearoa New Zealand (NZ). Methods: From the electronic health record of de-identified data for 374,071 men and women aged 18 and over enrolled as of 2014 in NZ general practices, any entry of recorded migraine from a patient’s visit to primary care or hospital facility recorded using Read codes, Read terms, or free text entries was extracted. Via an encrypted National Health Identifier (NHI), individual patient linkage identified migraine coded in the national hospitalisation dataset, enabling exploration by gender, age group, ethnicity and NZ deprivation index quintile. Results: Compared to population prevalence (15%), 4.8% of this cohort had recorded migraine (79% in general practice only; 14% in hospital records only; 7.5% in both primary and secondary care). Women (6.7%) had higher recording than men (2.5%), with the highest age-specific recording at 45–54 years (women 7.4%, men 2.7%). By gender and ethnicity, migraine recording was highest for European women (7.9%). Within quintile 5 communities (most deprived), recording was significantly lower for females ( p < 0.0001) and males ( p = 0.03) than in quintiles 1–4. Conclusions: This study is the first to estimate migraine in NZ using linked primary and secondary care data. As well as highlighting age-, gender-, and ethnicity-specific differences, the underestimate of diagnosis compared to self-reported survey data is likely due to health care access, under-reporting, under-diagnosis, under-recording, and knowledge gaps about migraine symptoms and therapies.

Objectives: This study examined whether incorporating free-text entries into structured general practice records improves the detection of long-term conditions (LTCs) and multimorbidity (MM) in New Zealand (NZ) general practices. Methods: Data from 374 071 deidentified individuals in general practices were analysed to identify 61 LTCs. Structured data were extracted using Read codes from a national master list, and clinical raters independently identified condition-related free-text, including synonyms, negation terms and common misspellings in randomised samples. Keywords were categorised and refined through ten iterative tests. Programmatic text classification was developed and assessed against gold-standard clinician ratings, using sensitivity, specificity, positive predictive value (PPV) and F ₁ -score. Results: A quarter of general practitioner classifications contained either unrecognised Read codes or consisted of free-text only. Clinician inter-rater reliability was high (kappa ≥0.9). Compared with clinical gold standard, text classification yielded an average sensitivity of 88%, specificity of 99% and PPV of 95%, with an F ₁ -score range of 82%–95%. Incorporating free text increased LTC prevalence from 42.1% to 46.3%, reducing misclassification of MM diagnoses by identifying 12 626 additional patients with MM and 15 972 additional patients with at least one LTC. Discussion: In the course of workflow, general practitioners face barriers to accurate LTC coding or may simply annotate with text-based descriptions. Programmatic text classification has demonstrated high performance and identified many more patients receiving LTC care. Conclusions: Combining structured and unstructured data optimises MM detection in NZ general practices and has the potential to improve case management, follow-up care and allocation of healthcare resources.

Background Cardiovascular disease (CVD) preventive medications are recommended for patients at high short-term CVD risk. As most younger people with multiple raised CVD risk factors levels have low short-term risk, they could be falsely reassured to take no action. Heart age—the chronological age of a hypothetical person with the same short-term absolute CVD risk as the patient being assessed, but with an ‘ideal’ risk profile—is a complementary relative CVD risk metric developed to encourage these younger patients to make long-term lifestyle changes. However, clinicians sometimes use heart age to inform medication decisions. We assessed the appropriateness of this practice by comparing heart age and short-term CVD risk. Methods New Zealand primary care patients are recruited to the PREDICT cohort when their CVD risk is assessed. PREDICT is an ongoing prospective study in one-third of New Zealand general practices, designed to derive CVD risk prediction algorithms. Five-year CVD risk was calculated for 35–74-year-old PREDICT participants using published equations. Heart age was calculated using non-smoking, systolic blood pressure of 120 mm Hg and total cholesterol/high-density lipoprotein ratio of 3.5, as the ‘ideal’ risk profile. CVD risk and heart age gaps (difference between chronological age and heart age) were compared. Results Among 371 676 PREDICT participants, 5-year CVD risk increased with age, approximately doubling every 10 years, whereas heart age gaps decreased with increasing age, approximately halving between 35 and 44-year olds and 65–74-year olds. There were 5–40-year heart age gap differences between groups with similar 5-year CVD risks, but different ages. Conclusion Short-term CVD risk and heart age are not interchangeable risk metrics. Short-term risk increases with increasing age whereas heart age gaps generally decline, with major differences between younger and older people with similar short-term risk. If heart age is used to inform medication decisions rather than encourage long-term lifestyle changes, older people at high short-term risk could be undertreated and younger people at low short-term risk could be unnecessarily medicated.

Background No routinely recommended cardiovascular disease (CVD) risk prediction equations have adjusted for CVD preventive medications initiated during follow-up (treatment drop-in) in their derivation cohorts. This will lead to underestimation of risk when equations are applied in clinical practice if treatment drop-in is common. We aimed to quantify the treatment drop-in in a large contemporary national cohort to determine whether equations are likely to require adjustment. Methods Eight de-identified individual-level national health administrative datasets in Aotearoa New Zealand were linked to establish a cohort of almost all New Zealanders without CVD and aged 30–74 years in 2006. Individuals dispensing blood-pressure-lowering and/or lipid-lowering medications between 1 July 2006 and 31 December 2006 (baseline dispensing), and in each 6-month period during 12 years’ follow-up to 31 December 2018 (follow-up dispensing), were identified. Person-years of treatment drop-in were determined. Results A total of 1 399 348 (80%) out of the 1 746 695 individuals in the cohort were not dispensed CVD medications at baseline. Blood-pressure-lowering and/or lipid-lowering treatment drop-in accounted for 14% of follow-up time in the group untreated at baseline and increased significantly with increasing predicted baseline 5-year CVD risk (12%, 31%, 34% and 37% in Conclusions CVD preventive treatment drop-in accounted for approximately one-third of follow-up time among participants typically eligible for preventive treatment (≥5% 5-year predicted risk). Equations derived from cohorts with long-term follow-up that do not adjust for treatment drop-in effect will underestimate CVD risk in higher risk individuals and lead to undertreatment. Future CVD risk prediction studies need to address this potential flaw.

Introduction: The volume and quality of online health information requires consumers to be discerning. Aim: This study aimed to explore consumer Internet use for health information, preferred format and what factors helped them to trust the source. Methods: A cross-sectional study was conducted in 2016–2017 with adults attending three cardiology outpatient clinic sites using a short paper-based survey. The survey included questions regarding online health information use and perceived trustworthiness with opportunities for free text responses. Survey data were summarised with key questions adjusted by age group, gender and ethnicity using logistic regression. Results: Of the 708 respondents (51% women, 66% aged 45–74 years, 16% Māori, 12% Pacific), 73% had sought health information online (64% in the previous 12 months), commonly for medication side effects, their health condition and self-help. Most (65%) were successful, although Pacific respondents reported a lower likelihood of search success compared to Europeans. Younger age groups were more concerned about information quality. Fact sheets (80%) were the most popular format and for all ethnic groups, followed by short videos (31%) and discussion groups (23%). Trusting online information required many strategies with 72% wanting health professionals to recommend websites. Discussion: Online health information seeking is a norm for consumers, with simple fact sheets being the preferred format to build knowledge and skills. With the rising tide of misinformation, health portal providers need to offer accurate and easy-to-read fact sheets in their suite of formats and health professionals need to support consumers guiding them to trusted websites.

Objective To examine the association of gout with cardiovascular outcomes using linked administrative health data in Aotearoa New Zealand. Design Data linkage study. Setting National registries of pharmaceutical dispensing, hospital admission, and deaths linked to the Auckland/Northland regional repository of laboratory results to create a regional health contact population as of 31 December 2011. Participants 942 416 residents of the Auckland/Northland region, aged 20-79 years with no history of cardiovascular disease. Main outcome measures Time to first fatal or non-fatal cardiovascular event, identified from national datasets on hospital admissions and mortality, between 1 January 2012 and 31 December 2016. Cardiovascular disease was broadly defined as comprising ischaemic heart disease, ischaemic or haemorrhagic stroke, transient ischaemic attack, peripheral vascular disease, and heart failure. Interventions A history of gout identified from a discharge diagnosis of gout from a public hospital admission or previous dispensing of gout specific drug treatments. The cohort was then linked to national hospital admissions and deaths through to 31 December 2016 (ie, 5 years' follow-up). Multivariable Cox proportional hazard models were constructed to assess the associations between gout, other risk factors, and cardiovascular outcomes. Results Of 942 416 people included in the study, 31 907 (3.4%) had gout (6261 women and 25 646 men). After adjustment for multiple risk factors for cardiovascular disease, gout was associated with increased cardiovascular events (adjusted hazard ratio 1.34 (95% confidence interval 1.23 to 1.45) in women; 1.18 (1.12 to 1.24) in men). For men with gout, there was an increased risk of cardiovascular disease in those who were not dispensed regular allopurinol (1.15 (1.05 to 1.25)) and those with a serum urate above the treatment target of 0.36 mmol/L (1.16 (1.04 to 1.30)). Risk of cardiovascular events was lower for men with gout who were not dispensed colchicine compared with those who were (0.84 (0.77 to 0.92)). These findings were not observed in women. Conclusion These results indicate that gout is associated with an increased risk of cardiovascular events. In men with gout without history of cardiovascular disease, the cardiovascular risk was lower in those regularly dispensed allopurinol and those with serum urate levels at the recommended treatment target. By contrast, colchicine dispensing was associated with an increased risk of cardiovascular events in men with gout without a cardiovascular history. The potential causal mechanisms of these associations require further exploration, including casual inference modelling in future studies.