Efeitos do abuso de álcool

See the separate related articles Alcoolismo e uso indevido de álcool - reconhecimento e avaliação e Alcoholism and alcohol dependence (Management).

In the UK, the Chief Medical Officers advise that adults should drink no more than 14 units of alcohol a week, spread evenly over 3 or more days. This is defined as 'low-risk' for health.¹

There is long-running controversy about whether or not low-level alcohol consumption may actually be protective for health. One example is the 'J-curve': the finding in some, but not all, epidemiological studies that light and moderate drinkers tend to have lower mortality rates than non-drinkers and heavy drinkers. The existence of a causal relationship is heavily disputed; there are several other plausible explanations for the association, such as that the reference group of 'non-drinkers' may be formerly-heavy drinkers who are now abstinent, or include people who avoid alcohol because they are already in poor health.²³

The World Health Organization's (WHO) current position is that there is no safe level of alcohol consumption, and that any degree of alcohol consumption has at least some risk to health, outweighing any positive effects.⁴

In 2022, 56% of adults in England reported drinking alcohol in the past week. 30% of men, and 15% of women, reported consistently drinking over the recommended weekly limit.⁵

Morbidity and mortality statistics for alcohol abuse⁵

In 2022-23 in England, there were just over 320,000 hospital admissions where the main reason for admission was drinking alcohol. Up to 15% of Emergency Department attendances are thought to be alcohol-related.

In the UK, deaths that are a direct consequence of alcohol ('alcohol-specific deaths') have increased by 70% between 2002 and 2022. In 2022, 10,048 alcohol-specific deaths were recorded.

• Death and illness from accident and injury, drowning, alcohol poisoning, and self-harm related to alcohol.

• Drinking five UK units on a single occasion more than doubles the relative risk of an injury in the six hours afterwards, and this relative risk rises even more rapidly when higher levels are consumed.

Câncer⁸

• Increased risk of some cancers, including:

  • Cânceres da cavidade oral.

  • Câncer de laringe.

  • Câncer de esôfago.

  • Câncer colorretal.

  • Câncer gástrico.

  • Liver cancer.

  • Câncer de mama.

• For female breast cancer, relative risks of both illness and death increase by 16% if drinking regularly at 2 units per day and by 40% if drinking regularly at 5 units per day.

• The lifetime risk of bowel cancer in men who drink at least 35 units weekly is almost double that of men who do not drink alcohol.

Doença cardiovascular⁹

• Fibrilação atrial.

• Hipertensão: Excessive alcohol use is associated with hypertension and subsequent target organ damage such as acidentes vasculares cerebrais, myocardial events e doença renal crônica.

• Cardiomiopatia dilatada com insuficiência cardíaca.

For cardiac arrhythmias in men, relative risks of illness and death from the disease increase by 13% if drinking regularly at 2 units per day and by 34% if drinking regularly at 5 units per day.

Doença hepática¹⁰

Alcohol accounts for over a third of all cases of liver disease. The three conditions most associated with alcohol use are fatty liver (steatosis), hepatitis (acute hepatitis and hepatite crônica), and cirrose.

Alcoholic cirrhosis is associated with a significant increase in risk of death due to bleeding oesophageal varices, infection, renal failure, and/or liver failure.

For cirrhosis of the liver in men, relative risks of death from the disease increase by 57% if drinking regularly at 2 units per day and by 207% if drinking regularly at 5 units per day.

Gastrointestinal tract¹¹

Alcohol increases the risk of oral cancers. This is especially associated with spirits and the risk is increased with concomitant use of tobacco. Adenocarcinoma of the stomach and oesophagus are thought to be related to alcohol use. Some of these cases may be genetically determined .

Hipertensão portal is a complication of cirrhosis and leads to a raised venous pressure in veins in the oesophagus and stomach. These swollen veins are superficial and bleed easily. Bleeding from oesophageal varices is serious and is associated with a high level of morbidity and mortality .

Management of bleeding varices is a medical emergency and requires adequate resuscitation (patients may need to be intubated to protect their airway). Blood transfusions are necessary and correction of abnormal clotting with vitamin K and fresh frozen plasma (FFP) may also be required. Various options for treatment are available including vasoactive drugs, endoscopic treatment including variceal ligation and sclerotherapy, and balloon tube tamponade.

Ambos pancreatite aguda e pancreatite crônica are associated with excessive alcohol consumption. One study found that consumption of spirits was more likely than wine or beer to cause acute pancreatitis. The pathophysiology of alcohol-related pancreatitis is not clearly understood. Patients usually present with epigastric pain with vomiting. The amylase is high in acute pancreatitis but may be normal in patients with chronic pancreatitis. Pancreatitis can be associated with a number of complications such as shock, sepsis and abscess formation. Long-term complications include diabetes mellitus and weight loss from steatorrhoea.

Sistema nervoso¹²

Acute alcohol intoxication can present with blackouts, head injuries and subdural haemorrhages. Alcohol withdrawal is associated with fits which may be unresponsive to antiepileptics.

O síndrome de Wernicke-Korsakoff results from lack of thiamine (commonly seen in those with alcohol dependency, due to malnutrition). Wernicke's syndrome occurs acutely and patients present with confusion, visual impairment (diplopia) and ataxia. Korsakoff's syndrome occurs more chronically and is characterised by memory deficits and confabulation .

Young people may be especially at risk of alcohol-induced brain impairment.¹³

Other adverse effects on the neurological system include peripheral neuropathy and cerebellar degeneration.

Psychiatric illness

Psychiatric conditions associated with alcohol misuse include:

• Alcohol dependence syndrome.

• Ideação suicida.

• Depressão.

• Ansiedade.

Approximately 44% of community mental health patients report problem drug use or harmful alcohol use in the previous year.

The National Confidential Inquiry into Suicide and Safety in Mental Health found that there was a history of alcohol misuse in 47% of people who died by suicide between 2011 and 2021. ¹⁴

Gravidez

Alcohol consumption during pregnancy can adversely affect the foetus:

• Foetal alcohol exposure can cause abortos espontâneos, natimorto, e restrição do crescimento intrauterino.

• Heavy drinking during pregnancy (repeatedly consuming more than around five units per day), can result in fetal alcohol spectrum disorders (FASD).

Sexual function¹⁵

Alcohol is associated with sexual dysfunction in men and women, including loss of libido and, in men, disfunção erétil e premature or delayed ejaculation.

Complicações sociais

• Social complications relating to alcohol misuse include:

  • Family conflict and domestic violence and abuse.

  • Impaired performance at work.

  • Problemas de relacionamento.

  • Violent crimes - for example, domestic violence and drink driving offences.

  • Comportamento antissocial.

Alcohol plays a part in 25-33% of known cases of child abuse.

In a study of four London boroughs, almost two thirds of all children subject to care proceedings had parents who misused substances, including alcohol.¹⁶

Alcohol withdrawal symptoms occur within a few hours of not having a drink and can last beyond 48 hours. Patients experience hallucinations, anxiety and a coarse peripheral tremor. On examination, patients may be pyrexial, tachycardic and hypertensive. They may also develop seizures and auditory and visual hallucinations.

Delirium tremens is the severe end of the spectrum of alcohol withdrawal and consists of a severe form of the above symptoms; it may be associated with circulatory collapse and ketoacidosis.

Veja o artigo separado sobre Abstinência aguda de álcool e delirium tremens artigo para mais detalhes.

This is characterised by the following:

• A strong desire to drink.

• Difficulty controlling alcohol intake.

• Physiological withdrawal when intake is reduced.

• Tolerance, such that increasing amounts are required to produce the same effect.

• Harm resulting from continued alcohol use - for example, work or relationship problems.

Treatment of alcohol dependence includes education, support, counselling and controlled alcohol withdrawal. Patients may need to be admitted to hospital for detoxification.¹⁷

Veja o artigo separado sobre Alcoholism and alcohol dependence - management artigo para mais detalhes.