Lucan · Conditions

SNAP lifestyle risk assessment

Australian guidance: RACGP SNAP — Smoking, Nutrition, Alcohol, Physical Activity

1. Definition and epidemiology

SNAP is a structured framework used in Australian general practice to assess and manage four modifiable behavioural risk factors: smoking, nutrition (including overweight and obesity), alcohol use, and physical inactivity. These four domains account for a disproportionate share of Australia's preventable disease burden, and they commonly cluster together in the same individual. Data from adult general practice encounters in 2013 to 2014 show that 62.7% of patients were overweight or obese, 13.5% were daily smokers, 23% drank at risky levels of alcohol, and approximately half had at least one of these three risk factors concurrently. Physical inactivity independently accounted for approximately 13,500 deaths in Australia in 2003 and contributed to around 7% of total disease burden. Risk factor burden is substantially higher in people from low socioeconomic backgrounds, those in rural and remote areas, and Aboriginal and Torres Strait Islander peoples.

2. Pathophysiology

Each SNAP domain exerts harm through distinct but overlapping mechanisms. Tobacco smoke delivers oxidants and carcinogens that promote endothelial dysfunction, accelerate atherosclerosis, increase platelet aggregability, and drive carcinogenesis across multiple organ systems via direct mutagenesis and chronic inflammation. Excess dietary saturated fat and energy intake drive visceral adiposity, which increases circulating free fatty acids, promotes hepatic insulin resistance, and sustains a low grade systemic inflammatory state mediated by adipokine dysregulation and elevated interleukin-6 and tumour necrosis factor alpha. Hazardous alcohol use causes direct hepatocyte toxicity through acetaldehyde accumulation, mitochondrial injury, and reactive oxygen species production, while also raising blood pressure via sympathetic activation and suppressing myocardial contractility in the longer term. Physical inactivity impairs skeletal muscle glucose uptake through reduced GLUT4 translocation, worsens dyslipidaemia by reducing lipoprotein lipase activity, and is independently associated with accelerated telomere shortening and all cause mortality. Because the four domains share downstream pathways centred on endothelial injury, systemic inflammation, and metabolic dysregulation, they potentiate each other's cardiovascular and oncogenic effects when they co occur.

3. Clinical presentation and diagnostic criteria

SNAP risk factors are largely asymptomatic until end organ damage supervenes, which makes opportunistic screening at every general practice encounter the primary detection strategy. The RACGP SNAP guide recommends that smoking status be assessed for every patient aged 10 years and older, and that alcohol intake be assessed in all patients aged 15 and older at least every two to four years. Body mass index (BMI) and waist circumference should be documented in the medical record at a minimum of every two years. Physical activity history should include type, frequency, duration, and sedentary time. High risk groups warranting more intensive assessment include pregnant women, Aboriginal and Torres Strait Islander peoples, people with existing cardiovascular disease (CVD) or diabetes, those with mental illness, and people from lower socioeconomic backgrounds. Nicotine dependence is suggested by smoking within 30 minutes of waking, more than 10 cigarettes per day, or withdrawal symptoms in prior quit attempts.

4. Investigations and AU-specific cutoffs

Assessment is primarily clinical and structured around the 5As model (Ask, Assess, Advise, Assist, Arrange). Validated screening tools recommended in the RACGP SNAP guide are listed below.

Smoking: document status (current, ex, never) and quantify pack years. Markers of dependence include time to first cigarette, daily cigarette count, and prior withdrawal history.

Nutrition and weight: measure BMI (weight in kg divided by height in metres squared) and waist circumference at the end of normal expiration, midway between the inferior rib margin and the iliac crest in the mid axillary plane. AU cutoffs for waist circumference: increased risk at more than 94 cm (male) or more than 80 cm (female); high risk at more than 102 cm (male) or more than 88 cm (female). BMI classification: underweight less than 18.5 kg/m2, normal 18.5 to 24.9 kg/m2, overweight 25 or greater, obese I 30 to 34.5, obese II 35.0 to 39.9, obese III 40 or greater. In Asian populations, increased metabolic risk may begin at BMI greater than 23 kg/m2. Blood pressure should be measured in all patients aged 18 and older; lipids in those aged 45 and older. Absolute CVD risk should be calculated using the National Vascular Disease Prevention Alliance calculator at www.cvdcheck.org.au.

Alcohol: use the Alcohol Use Disorders Identification Test (AUDIT) or the briefer three item AUDIT-C. AUDIT-C scoring: positive in men at 4 or more and in women at 3 or more. A full AUDIT score of 20 or more (or AUDIT-C 5 or more) should prompt consideration of assessment for assisted withdrawal. An Australian standard drink contains 10 g of alcohol, equivalent to 12.5 mL of pure alcohol.

Physical activity: enquire about minutes of moderate and vigorous activity per week and daily sedentary time.

5. Management

The RACGP SNAP guide structures management around the 5As model applied to each domain. Brief advice delivered by a GP during a routine consultation is more effective than no intervention across all four domains, and interventions are most effective when the patient is motivated and supported with follow up. Motivational interviewing, which resolves ambivalence through non confrontational dialogue, is an evidence based communication strategy recommended for use across all SNAP domains.

Smoking: all patients who smoke should receive brief cessation advice regardless of quantity smoked. Patients ready to quit should agree on a quit date, identify triggers, and be prescribed pharmacotherapy if eligible. Follow up at one week and one month after the quit date is recommended to reduce relapse. Quitline (13 7848) provides telephone counselling and a Quit Coach service.

Nutrition: advise patients to follow the Australian Dietary Guidelines, targeting at least five serves of vegetables and two serves of fruit per day. For weight loss, a target energy deficit of approximately 2,500 kilojoules per day is used to guide dietary intervention, with emphasis on reducing saturated fat and high sugar foods. A target weight loss of 1 to 4 kg per month in the short term and 5 to 10% of initial body weight in the long term is appropriate. Patients with obesity and comorbidities may be referred to a dietitian via the Dietitians Association of Australia (1800 812 942).

Alcohol: advise all adults to drink no more than two standard drinks per day and no more than four on any single occasion. Pregnant women should be advised that non drinking is the safest option. Brief motivational counselling should be offered to patients drinking at risky or high risk levels. Patients with more severe alcohol dependence should be referred to local drug and alcohol counselling services.

Physical activity: encourage adults to accumulate at least 150 minutes of moderate intensity activity per week, or 75 minutes of vigorous intensity activity, or an equivalent combination. A physical activity prescription negotiated with the patient and referral to an exercise physiologist may be arranged under a GP Management Plan or Team Care Arrangement.

6. Pharmacology and AU PBS notes

Smoking cessation pharmacotherapy is indicated in all motivated smokers with evidence of nicotine dependence smoking more than 10 cigarettes per day.

Nicotine replacement therapy (NRT): available as patches, gum, lozenge, inhaler, and mouth spray. All NRT monotherapy formulations have similar efficacy, increasing sustained quit rates by approximately 60% compared with placebo. Combining a nicotine patch with an oral NRT form is more effective than monotherapy and is recommended when monotherapy fails. Pre cessation patching, commencing two weeks before the quit date, further improves outcomes. NRT is contraindicated in those with recent acute myocardial infarction, severe or worsening angina, recent stroke, or serious arrhythmia. Available over the counter; no PBS restriction code required.

Varenicline (Champix): the most effective monotherapy, more than doubling sustained abstinence at six months compared with placebo. Dose is titrated upward over one week to reduce nausea, which occurs in approximately 30% of users. Meta analysis shows no significant increase in neuropsychiatric adverse events compared with placebo. PBS listed for smoking cessation (no streamlined authority code; standard authority required).

Bupropion (Zyban): effective in combination with behavioural support. Contraindicated in patients with seizure disorders, anorexia or bulimia, CNS tumours, or monoamine oxidase inhibitor use within 14 days. Use with caution in patients with recent head trauma, diabetes, renal impairment, or those taking drugs that lower seizure threshold. PBS listed.

Alcohol dependence pharmacotherapy (after assisted withdrawal): acamprosate and oral naltrexone are first line agents for moderate to severe dependence, used in conjunction with cognitive behavioural therapy or other structured psychological intervention. Both are contraindicated in pregnancy and in severe liver or renal disease. PBS listed.

Orlistat (Xenical): an adjunct to lifestyle intervention for obesity with BMI greater than 30 kg/m2, or greater than 27 kg/m2 with comorbidities. Inhibits pancreatic lipase. Not PBS listed for general obesity at the time of the SNAP guide publication; prescriber check required.

7. Complications and monitoring

Failure to address SNAP risk factors collectively drives the majority of preventable chronic disease burden in Australia. Key downstream complications include ischaemic heart disease, stroke, type 2 diabetes mellitus, chronic obstructive pulmonary disease, multiple cancers (lung, colorectal, oropharyngeal, oesophageal, breast), alcoholic liver disease, cirrhosis, peripheral vascular disease, osteoporosis, and depression.

Monitoring schedule by domain:

Smoking: review at one week and one month after quit date; ongoing opportunistic assessment at all encounters.

Nutrition and weight: review diet and weight management plan at two weeks after initiation; thereafter every two to three months to sustain dietary change; yearly review over five years following weight reduction.

Alcohol: review one to three months after initial assessment to monitor progress and revise goals; most behavioural relapses occur within the first few weeks, so early follow up is prioritised.

Physical activity: review progress at the next scheduled consultation; incorporate activity monitoring into chronic disease management plans where applicable.

Absolute CVD risk should be recalculated periodically using the National Vascular Disease Prevention Alliance calculator to contextualise the aggregate impact of risk factor modification across all SNAP domains. Patients with complex needs and chronic comorbidities may benefit from a GP Management Plan and Team Care Arrangement under Medicare's Chronic Disease Management GP services to coordinate allied health input across domains.

Written for Australian practice and grounded in the guidance named above. Study material only — not medical advice. Always check against current guidelines.