What are the common primary care medication regimens for managing hypertension, diabetes, asthma, and hyperlipidemia in New Zealand?

From the Guidelines

In New Zealand, primary care management of common chronic conditions such as hypertension, diabetes, asthma, and hyperlipidemia follows specific medication regimens that prioritize morbidity, mortality, and quality of life as outcomes. For hypertension, first-line treatments typically include ACE inhibitors (cilazapril, enalapril), calcium channel blockers (amlodipine), and thiazide diuretics (bendroflumethiazide), usually starting at low doses and titrating upward as needed to achieve target blood pressure below 130/80 mmHg, as recommended by the most recent guidelines 1. Key considerations for hypertension management include:

• Prompt initiation and timely titration of pharmacologic therapy for patients with confirmed office-based blood pressure ≥140/90 mmHg, with a focus on drug classes demonstrated to reduce cardiovascular events in patients with diabetes, such as ACE inhibitors, angiotensin receptor blockers, thiazide-like diuretics, or dihydropyridine calcium channel blockers 1.
• The use of multiple-drug therapy to achieve blood pressure targets, while avoiding combinations of ACE inhibitors and angiotensin receptor blockers, and combinations of ACE inhibitors or angiotensin receptor blockers with direct renin inhibitors 1. Diabetes management begins with metformin (500mg daily, increasing to 1000mg twice daily as tolerated) as first-line therapy, with sulfonylureas like gliclazide added as second-line agents. For asthma, treatment follows a stepwise approach, starting with as-needed short-acting beta-agonists (salbutamol) and progressing to regular inhaled corticosteroids (fluticasone, beclomethasone) for persistent symptoms. Hyperlipidemia is primarily managed with statins, with atorvastatin (10-80mg daily) and simvastatin (10-40mg daily) being the most widely used, and treatment targets are based on cardiovascular risk assessment rather than absolute lipid levels. These medication regimens are typically accompanied by lifestyle modifications including dietary changes, regular physical activity, smoking cessation, and alcohol moderation, which are considered fundamental components of managing all these conditions in the New Zealand healthcare context. The most recent and highest quality study, published in 2021, provides the basis for these recommendations, emphasizing the importance of evidence-based practice in primary care 1. In terms of specific medication regimens, the following are commonly used in New Zealand:
• Hypertension: ACE inhibitors, calcium channel blockers, and thiazide diuretics
• Diabetes: metformin, sulfonylureas, SGLT-2 inhibitors, and GLP-1 agonists
• Asthma: short-acting beta-agonists, inhaled corticosteroids, and combination inhalers
• Hyperlipidemia: statins, with atorvastatin and simvastatin being the most widely used. It is essential to note that these regimens should be tailored to individual patient needs and circumstances, taking into account factors such as comorbidities, medication interactions, and patient preferences. Ultimately, the goal of primary care management is to improve patient outcomes, reduce morbidity and mortality, and enhance quality of life, and the medication regimens outlined above are designed to achieve these objectives 1.

From the Research

Common Primary Care Medication Regimens in New Zealand

• Hypertension: According to 2, alternative step I antihypertensive agents such as alpha 1-blockers, ACE inhibitors, and calcium channel blockers can be used to manage hypertension, especially in patients with hyperlipidemia. However, 3 suggests that thiazide-type diuretics are superior in preventing major forms of cardiovascular disease and are less expensive, making them a preferred choice for first-step antihypertensive therapy.
• Diabetes: 4 found that structured care with a multi-interventional approach, including lifestyle programs and targeted pharmacological treatment, can effectively reduce cardiovascular risk factors and improve glycemic control in patients with Type 2 diabetes.
• Asthma: There is no direct evidence provided for asthma management in New Zealand. However, general guidelines for asthma management typically involve a stepwise approach for controlling symptoms and preventing exacerbations.
• Hyperlipidemia: 2 suggests that managing hyperlipidemia is crucial in patients with hypertension, and alternative step I antihypertensive agents that do not interfere with lipid therapy should be chosen.

Guidelines for Managing Long-Term Conditions in New Zealand

• 5 found that formal collaborative methodologies, such as the Breakthrough Series methodology, can improve quality in primary health care in New Zealand by facilitating planned care, promoting quality improvement, and improving clinical outcomes for patients with long-term conditions.
• The study 5 also highlights the importance of strengthening facilitation processes, improving access to comprehensive population audit tools, and lengthening the time frame for quality improvement programs to make significant improvements in practice.

Medication Regimens for Specific Conditions

• For hypertension, 3 recommends the use of chlorthalidone, amlodipine, or lisinopril as first-line treatment options, with the choice of medication depending on patient variables such as age, race, and concomitant diseases.
• For diabetes, 4 suggests that a structured care approach with lifestyle programs and targeted pharmacological treatment can improve glycemic control and reduce cardiovascular risk factors.
• For hyperlipidemia, 2 recommends managing lipid levels in patients with hypertension, and choosing antihypertensive agents that do not interfere with lipid therapy.

Future Directions

• 6 highlights the need for additional precision medicine work to identify factors associated with the effectiveness of commonly used antihypertensive medications, and to develop more effective treatment strategies for patients with hypertension.
• Further research is needed to develop evidence-based guidelines for managing asthma and other long-term conditions in New Zealand, and to evaluate the effectiveness of different medication regimens and treatment approaches in primary care settings.