What are the most frequently used guidelines in primary care for managing common conditions such as hypertension (High Blood Pressure), diabetes (Diabetes Mellitus), and respiratory infections?

Most Frequently Used Guidelines in Primary Care

Hypertension Management

The most frequently used hypertension guidelines in primary care are the VA/DoD 2020 guidelines and ACC/AHA guidelines, which define hypertension as BP ≥140/90 mmHg and recommend comprehensive cardiovascular risk assessment to guide treatment decisions. 1, 2, 3

Blood Pressure Measurement and Diagnosis

• Measure blood pressure at every routine clinical visit, with patients seated, feet flat on floor, arm supported at heart level, after 5 minutes of rest, using appropriate cuff size 3
• Confirm elevated readings on a separate day before diagnosing hypertension (except when BP ≥180/110 mmHg with cardiovascular disease) 3
• All adults should have BP measured routinely at least every five years until age 80 years 1
• Patients with "high normal" BP (130-139/85-89 mmHg) require annual monitoring 1

Treatment Thresholds

• Initiate drug therapy at BP ≥140/90 mmHg for confirmed hypertension 1, 2, 3
• For high-risk patients (diabetes, CKD, cardiovascular disease), start treatment at BP ≥130/80 mmHg 2, 3
• For patients with elevated BP (120-139/<80 mmHg) and high cardiovascular risk, initiate pharmacological treatment if BP remains ≥130/80 mmHg after 3 months of lifestyle intervention 2

Blood Pressure Targets

• Target systolic BP to 120-129 mmHg for most adults to reduce cardiovascular disease risk, if well tolerated 2
• For adults ≥65 years, target <130 mmHg systolic 3
• For patients with diabetes or CKD with eGFR >30 mL/min/1.73m², target systolic BP to 120-129 mmHg 2

First-Line Pharmacological Treatment

• Preferred initial combination: RAS blocker (ACE inhibitor or ARB) with either a dihydropyridine calcium channel blocker or thiazide/thiazide-like diuretic, preferably as a single-pill combination 2
• First-line drug classes include thiazide diuretics, ACE inhibitors, ARBs, and calcium channel blockers 2, 3, 4
• Reserve beta-blockers for specific indications (angina, post-MI, heart failure, heart rate control) 2

Treatment Escalation

• If BP not controlled with two-drug combination, escalate to three-drug combination: RAS blocker + dihydropyridine CCB + thiazide/thiazide-like diuretic 2
• Never combine two RAS blockers (ACE inhibitor and ARB), which is potentially harmful 2

Lifestyle Modifications

• Adopt Mediterranean or DASH diet patterns emphasizing fruits, vegetables, and low-fat dairy products 2
• Reduce sodium intake and increase potassium intake (0.5-1.0 g/day) to achieve sodium-to-potassium ratio of 1.5-2.0 2
• Regular aerobic exercise can lower systolic BP by 7-8 mmHg and diastolic BP by 4-5 mmHg 2
• Aim for BMI 20-25 kg/m² and waist circumference <94 cm in men, <80 cm in women 2
• Limit alcohol consumption, preferably avoiding it completely 2

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Diabetes Management

Metformin is the first-line pharmacological agent for type 2 diabetes, working by improving insulin sensitivity, decreasing hepatic glucose production, and reducing intestinal glucose absorption. 5

Metformin Use

• Metformin helps control blood sugar by improving the body's response to insulin, decreasing liver glucose production, and decreasing intestinal glucose absorption 5
• Metformin does not cause the body to make more insulin 5
• Effective in children ages 10-16 years with type 2 diabetes 5
• Should be taken with meals to lessen gastrointestinal side effects 5

Contraindications to Metformin

• Do not use metformin in patients with kidney problems, as this increases risk of lactic acidosis 5
• Avoid in patients with type 1 diabetes or diabetic ketoacidosis 5
• Stop temporarily before procedures requiring contrast dye or surgery with prolonged fasting 5
• Use caution in patients over 80 years unless kidney function is confirmed normal 5
• Avoid with heavy alcohol consumption 5

Diabetes and Hypertension Comorbidity

• Up to 75% of adults with diabetes also have hypertension, sharing overlapping risk factors and complications 6
• Management requires addressing hyperglycemia, hypertension, dyslipidemia, and underlying hypercoagulable states with multiple medications 6
• For diabetic patients with hypertension, ACE inhibitors or ARBs are reasonable first-line agents 3

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Respiratory Tract Infections

Antibiotics should not be routinely prescribed for acute lower respiratory tract infections in primary care; amoxicillin or tetracycline are first-choice when antibiotics are indicated. 1

Diagnosis and Risk Assessment

• C-reactive protein (CRP) <20 mg/L at presentation with symptoms >24 hours makes pneumonia highly unlikely; CRP >100 mg/L makes pneumonia likely 1
• In case of persisting doubt after CRP testing, obtain chest X-ray to confirm or reject pneumonia diagnosis 1
• Microbiological tests such as cultures and gram stains are not recommended in primary care 1

Risk Factors for Complications

• In patients over 65 years, risk factors include: COPD, diabetes, heart failure, previous hospitalization in past year, oral glucocorticoids, recent antibiotic use, general malaise, absence of upper respiratory symptoms, confusion, pulse >100, temperature >38°C, respiratory rate >30, BP <90/60 mmHg 1
• In patients under 65 years, diabetes, pneumonia diagnosis, and possibly asthma are risk factors for complications 1

Symptomatic Treatment

• Do not prescribe cough suppressants, expectorants, mucolytics, antihistamines, inhaled corticosteroids, or bronchodilators for acute LRTI in primary care 1

Antibiotic Indications

• For COPD exacerbations, prescribe antibiotics when all three symptoms present: increased dyspnoea, sputum volume, and sputum purulence 1
• Consider antibiotics for exacerbations in patients with severe COPD 1

Antibiotic Selection

• Amoxicillin or tetracycline should be first-choice antibiotics based on least chance of harm and wide clinical experience 1
• For penicillin hypersensitivity, use tetracycline or macrolide (azithromycin, clarithromycin, erythromycin, roxithromycin) in countries with low pneumococcal macrolide resistance 1
• Consider national/local resistance rates when choosing antibiotics 1
• When clinically relevant bacterial resistance exists against all first-choice agents, consider levofloxacin or moxifloxacin 1

Hospital Referral Criteria

• Refer severely ill patients with suspected pneumonia (tachypnoea, tachycardia, hypotension, confusion) 1
• Refer patients with pneumonia failing antibiotic treatment 1
• Refer elderly patients with pneumonia and elevated complication risk, particularly those with diabetes, heart failure, moderate-severe COPD, liver disease, renal disease, or malignancy 1