Cold, health, admissions and
Greg Fell, NW Leeds PCT
0113 3057 548
Purpose of this presentation
• Support to a Winter 06 project to reduce
cold related admissions and death.
• Overview of effects of cold on health,
morbidity, mortality and quality of life
• Overview of key interventions to address,
both warmth and clinical.
• Overview of what is being done in W
Yorks in Winter 2005 / 2006
• Most people and many doctors have difficulty in recognising the
importance of cold. As a nation we are poorly educated about the
effects of cold and how to deal with it.
• This probably contributes to the poor record of our high extra winter
mortality and this may be exacerbated by the run of recent mild
• Nationally we have a tendency for warmer winters than elsewhere in
• The quality (primarily insulation and thermal efficiency) of the UK
housing stock is well below that in Northern Europe.
• Therefore we live in colder homes. When we go outside, we are less
likely to wrap up.
Effects of Cold on Health
1. Excess Winter Mortality – primarily cardiovascular and respiratory
2. Admission –
• respiratory illness / hypothermia / cardiovascular illness following a cold snap.
3. Consultation – particularly GPs
• approximately 8% householders (Leeds City Council data) feel their health has
been affected by cold in their home. A likely under estimate
4. Quality of life
– there is consistent anecdotal evidence re families sleeping and living on one
room in winter due to inability to heat house
5. Educational attainment –
• there are many local examples of children not doing homework due to living in
cold conditions. Longer term impact on health – poor educational attainment
leads to lower adult income.
1 Excess Winter Mortality
Excess Winter Mortality (EWM) –
key facts (1)
• EWM compares the 4 months of Dec to Mar with the preceding and
following 4 month periods.
• There is a 40% difference between the peak death rate in Winter with the
lowest death rate in Summer.
• There is a linear relationship of temperature and mortality (a 1.4%
increase in mortality for every 1°C fall in temperature from 18°C.)
– This means that all winter days not just the coldest that create some
• There are approximately 810 Excess Winter Deaths in W Yorkshire per
year (ONS – EWM for 2002 / 03)
• For every 1 degree fall in the winter average air temperature, there is an
approximate one fifth increase in excess winter deaths – 5,000 deaths
nationally, 162 deaths in West Yorkshire.
• It has been consistently suggested that cold, and particularly cold damp
homes, are a major contributory factor to 80% of excess winter deaths.
EWM – key facts (2)
• The UK has one of the largest increases in mortality during cold weather compared to
other countries in Europe. This is due to the fact that during cold weather people:
– don’t maintain their body temperature since they don’t wear enough clothing,
especially when outdoors
– are less active
– live in colder houses - living rooms in the UK are colder, bedrooms are less likely
to be heated
compared to their counterparts in colder countries.
• The Eurowinter study demonstrated that a mild climate was no protection to extra
winter deaths. London has double the excess winter mortality compared to colder
– Also see: Pattenden S. JECH, 2003. comparison of EWM between Sophia and London. Higher increas in EWM in response to cold temperatue
in London compared to the conditions in Sophia
• In the coldest countries, at 7°C people were more likely to wear anoraks hats and
gloves and were more active compared to London at the same temperature.
• thought that indoor temperature (rather than outdoor) is key factor affecting
– much colder countries have lower rates of excess winter mortality than the UK.
Trends in excess winter death
•Rate has fallen continually since 1950s. Still a significant number
•Approx 23,000 in 2003 / 4
Seasonal pattern and spikes in EWM – W Yorkshire
Deaths in Hospital Following Emergency Admissions for Selected Seasonal Primary Diagnoses
Number of Deaths
Jul- Aug- Sep- Oct- Nov- Dec- Jan- Feb- Mar- Apr- May- Jun- Jul- Aug- Sep- Oct- Nov- Dec- Jan- Feb- Mar- Apr- May- Jun- Jul- Aug- Sep- Oct- Nov- Dec- Jan- Feb- Mar-
02 02 02 02 02 02 03 03 03 03 03 03 03 03 03 03 03 03 04 04 04 04 04 04 04 04 04 04 04 04 05 05 05
Septicaemia, unspecified Bronchopneumonia, unspecified
Pneumonia, unspecified Unspecified acute lower respiratory infection
Chronic obstruct pulmonary dis with acute lower resp infec
Time lag and EWM (and Admission)
• It is possible to predict with a high degree of accuracy the time lag
between a cold snap and admissions / excess winter deaths.
• After a cold snap
• 2 to 5 days – peak in EWM and admission for Cardiovascular
– Heart Attack - 2 days
– Stroke - 5 days
• 10 – 12 days - peak in EWM and admission for Respiratory
• This relationship is consistent in other temperate countries. The
three and twelve day lags mark the peak death days, surrounded by
a relatively normal distribution.
Age Distribution of EWM
• Particularly an issue for over 65s.
• 43% of excess winter deaths occurring in
the 85+ population, who make up approx
2% of the population.
• This is in contrast to 8.5% of excess winter
deaths occurred in the 0-64 population
who make up 95% of the total population.
Causes of EWM
• 810 deaths in W Yorks
• Approximately 80% are strongly influenced or possibly caused by cold,
particularly living in a cold, damp home.
• Of the COLD RELATED EWM
• Cardiovascular disease accounts for approx 62% of the cold related excess winter
– Heart attack – accounts for 47% - deaths . generally occurring 2 days after a
– Stroke – accounts for 15% - deaths - generally occurring 5 days (for stroke)
after a cold snap.
• Respiratory disease - accounts for approx 37% of the cold related excess winter
– Influenza (non epidemic years) – 17%
– Other (including COPD) – remainder
• Hypothermia - accounts for 2% of excess winter deaths
2 Morbidity and Admission
Morbidity and Excess Winter
• There are strong associations between cold or damp living
conditions and worsening illness.
• Admission data clearly shows that there are peaks in admissions,
particularly for respiratory / cardiovascular / hypothermia, following a
• Approximately 8%, or 5000 householders feel their, or a member of
their families, health has been affected by cold conditions in the
– This is most often for those living in private rented sector homes –
where energy efficiency is often poor.
– Twice as many residents of private rented (compared to owner
occupied) reported their families health had been affected by cold
conditions in their home
Excess Winter Admissions – W Yorkshire
Peaks in winter Emergency Admissions for Selected Seasonal Primary Diagnoses
Number of Emergency Admissions
J Au Se Oc No De Ja Fe Ma Ap Ma Ju J Au Se Oc No De Ja Fe Ma Ap Ma Ju J Au Se Oc No De Ja Fe Ma
ul- g- p- t- v- c- n- b- r- r- y- n- ul- g- p- t- v- c- n- b- r- r- y- n- ul- g- p- t- v- c- n- b- r-
02 02 02 02 02 02 03 03 03 03 03 03 03 03 03 03 03 03 04 04 04 04 04 04 04 04 04 04 04 04 05 05 05
Rotaviral enteritis Viral intestinal infection, unspecified
Diarrhoea and gastroenteritis of presumed infectious origin Bronchopneumonia, unspecified
Lobar pneumonia, unspecified Pneumonia, unspecified
Acute bronchiolitis, unspecified Unspecified acute lower respiratory infection
Chronic obstruct pulmonary dis with acute lower resp infec Febrile convulsions
W Yorkshire HA Analysis of Excess Winter Admission
Average Winter Average Summer Excess Winter Excess Winter
Primary diagnosis Month Admissions – Month Admissions Admissions / Admissions –
WY –WY month
Rotaviral enteritis 16.0 4 12 48
Viral intestinal infection, unspecified 103.6 71 32 129
Diarrhoea and gastroenteritis of presumed 62.8 49 14 56
Bronchopneumonia, unspecified 40.3 28 12 49
Lobar pneumonia, unspecified 190.5 142 48 194
Pneumonia, unspecified 156.9 115 41 166
Acute bronchiolitis, unspecified 102.2 32 70 281
Unspecified acute lower respiratory 352.2 263 89 355
Chronic obstruct pulmonary dis with acute 201.1 149 52 209
lower resp infec
Febrile convulsions 42.3 33 9 37
Unknown and unspecified causes of 1141.7 362 1048 4195
TOTAL 2409 1248 1427 5719
Over whole winter period (4 months). 5719 Excess Winter Admissions per
year. Averaged over last 3 years.
8% of householders feel their health has
been affected by cold conditions
Do you feel that your health or that of your family's is affected by
cold conditions in your home?
Owner Occupier Housing Privately Rented All tenures
Morbidity, and admission
• Cold, damp living conditions does have a significant impact on illness, admission, and poor
quality of life. The effect of cold homes on risk of illness and quality of life are reviewed
Health Risk Effect
Increased respiratory Temperatures below 16ºC are thought to lower resistance to respiratory infection.
Worsening asthma, and Damp leads to growth of moulds and fungi which can cause allergies and respiratory infections. Fifteen
COPD per cent of homes report mould. NB these are UK figures. Studies in the early 1990s in Leeds showed
that 27% of homes report mould.
The cold impairs lung function and is an important trigger of broncho-constriction in asthma and COPD.
People with asthma are two to three times more likely than the general population to live in damp
Increased blood Blood pressure rises in older people with exposure to temperatures below 12ºC.
pressure and risk of
heart attacks / strokes The risk of heart attacks and strokes increases with increasing blood pressure. In those aged 65-74
years, a 1ºC decrease in living room temperature is associated with a rise of 1.3mmHg systolic blood
pressure and a rise of 0.6 mmHg diastolic blood pressure.
Worsening arthritis Symptoms of arthritis, particularly pain, become worse among people who live in cold, damp homes.
Increased accidents at Having a cold home increases the risk of falls in the elderly, and the risk of accidents due to loss of
home strength and dexterity in the hands and due to open or free-standing heating. Finger strength and
manual dexterity fall progressively in temperatures from 24ºC to 6ºC.
When accidents do occur – people who have fallen and are unattended to living in a cold damp home
are more likely to suffer complicating factors.
Social isolation People may become more socially isolated due to economising and reluctance to invite friends into a
cold home. Increased social isolation is an independent risk factor for depression and coronary heart
disease, mental illness, reduced quality of life.
Adverse effect on Homes in fuel poverty have a choice between keeping warm and spending money on other essentials.
nutrition Poor diet can be the result, with increased long-term health risks of cancer and coronary
3 GP Consultation
• Association between low temperature and LRTI consultations.
– Particularly 65+ population
– For every 1oc drop in mean temperature below threshold of 5oc – a
19% increase in LRTI consults.
– 0 – 20 day time lag between drop in temp below threshold and consult.
– Weaker association between URTI consultations and drop in
– North / South Divide. Larger effect in Northern England
– Hajat – Shakoor et al. Int J Epid, 2004, 19 (10) p959
• Strong association between temperature 15 days previously and
increase in consultations. Particularly as temperature falls below 5oc
– For every 1oc drop in temp below 5oc - consults for all respiratory
problems increased by 10% (95% CI 7.6% – 13.4%)
– No apparent relationship between falling temp and cardiovascular
consults. ? More likely acute admission
Hajat S, Haines A. Int J Epid, 2002, 31 (4) p 825
Physiology, temperature (indoor
and out), key population groups
• causes blood pressure, red blood cells, platelets and fibrinogen
to increase –
• predispose to formation of clots – heart attack and stroke.
• The elderly most at risk of thermoregulatory problems
• Damp – much less clear
• Allergies to mould - rhinitis, alveolitis, itching, sneezing,
wheezing, conjunctivitis, fever, coughing, fibrosis, cardiovascular
• Infections - flu-like symptoms to irreversible lung damage
Outdoor and indoor temperature – what
is the difference. Which is important?
• Indoor temperature is clearly linked to outdoor air temperature, however the
ability to heat a home is modified by housing condition (thermal and
energy efficiency), fuel prices and household income – all modifiable.
• There is a strong link between older houses (more difficult to keep warm)
and excess winter death.
• There is a 20% difference in excess winter death between people living in
the most and least thermally efficient homes
• Excess winter deaths are significantly more likely in people living in
old houses; they are harder to heat to a decent standard.
• Compared with other countries; living rooms in the UK are colder,
bedrooms are less likely to be heated and when we do go outside in
cold temperatures, we are less likely to wear warm clothing
Risk Temperatures - EWM
Linear relationship between decreasing temp and EWM (a 1.4% increase in mortality
for every 1°c fall in temperature from 18°C.).
– This means that all winter days not just the coldest that create some excess
• Nahya S. Int J Circumpolar H. 2002
• EWM – Cardiovascular and respiratory
– Strongest association between falling temperature and
– Still mainly linear relationship
– Rate of increase (of EWM) steepen below 11oc
– For temp below 11oc, a 1oc fall in daytime mean
temperature was associated with an increase in mortality
• 2.9% (95% CI 2.5 – 3.4) – all cause
• 3.4% (95% 2.6 – 4.1) – cardiovascular
• 4.8% (95% 3.5 – 6.2) – respiratory
• 1.7% (95% 10. – 2.4) – other cause
Over the following month.
Wind chill does not have significant impat. Dry bulb temp seems to be the key factor.
Carder M et al. Occup Env Med, 2005
Indoor thermal comfort
• Indoor temp risk markers are set
> 18°c - Adequate warmth. No risk to
sedentary, but otherwise healthy individuals
< 18°c – discomfort
< 15°c – increased risk of respiratory
infection – reduced resistance to infection
< 12°c – increased risk of heart attack /
stroke – increase in blood viscosity
< 9°c – reduced core temp. risk of
Indoor temperatures recommended for
(see Health and Safety Rating System for home hazard assessment):
Minimum to maintain health Standard to achieve comfort
Living Room 11 °c 21 °c
Other used rooms 10 °c 18 °c
Consider these temperature risk markers when in a patients home.
• Older people – 65+ especially
• Young children and babies
• People with respiratory illnesses
• People with established cardiovascular disease
• People with established long term condition / chronic illnesses
• People with disabilities
• People with mobility difficulties
• People without access to advice& information
• Patients leaving hospital – particularly from above groups
• Asylum Seekers – more likely to have poor accommodation?
• Keep Warm / Keep Well
• Cover for wide range of winter warmth interventions,
– Keeping the house warm
– Cold outdoor temperatures. Wrapping up!
– Early reporting of symptoms.
– Available medication – ensuring there is some
– Physical activity / Diet / hot drinks etc.
– Social Support
– Flu jab
– Stop smoking
– Home energy efficiency / thermal comfort
• Over and above the standard Keep Warm message, it is difficult to be
precise with regard to clinical advice given to patients with specific
• Clinical judgment is necessary – but consider how will, or could, cold affect
– With knowledge of physiology, ability to get out to a pharmacy or GP,
– What support is available to the patient – family, friends, carers, neighbours to
– Does the patient have the ability to deal adequately with an exacerbation of their
condition? Will they know what to do? Is their carer aware?
– Has the patient been through a self management course? Consider their ability
to self manage
– Is there a formal self management plan in place
– Encourage early reporting of symptoms – ie don’t wait until it is an emergency!
– Keep active
– Consider the value of having a reserve of any medications – eg for COPD
patients – keep a reserve of antibiotics and steroids (data indicates that 60% will
be receptive to this)
Impact of interventions
• Flu immunisation - very good evidence of effect
• Smoking cessation – as above
• Fuel poverty eradication - the evaluation of 'Warm Front', soon to
be published, shows insulation and central heating installation in
eligible households to be cost effective, particularly in relation to
morbidity and wellbeing, but also in relation to CV mortality
• Behavioural - good evidence from a range of studies that wrapping
up, keeping moving outside, sleeping in an adequately heated
bedroom (ie with the window shut!) all make a difference.
What is being done in W Yorks?
Agreement to trial an early warning system with regard to cold conditions. Based
on some work done by Met Office
• Twice weekly review of meteorological information and risk management by Leeds
North West PCT Public Health staff
• Twice weekly 'cold alert' bulletin when appropriate by e-mail to key PCT contacts
(Winter Planning Lead and/or LA contact, and/or providers)
• Onward urgent alert by PCT lead to relevant staff e.g., Community Matrons, Care
Support Workers etc.,
• "Keep Warm, Keep Well", simple message emphasised to relevant identified patients
• Active identification of ‘high risk of admission’ patients – consideration of
usefulness of calling them to emphasise Keep Warm Keep Well and key clinical
advice pertinent to cold conditions.
• Passive dissemination of message to wide variety of health, social care and other
agencies – cascade onto their patients / clients / users as possible and appropriate
• Use of media – particularly local weather bulletins.
• Ongoing media support through Winter period.
Materials to support
• A 2-side fact sheet will be prepared for
clinicians. Weekly temperature predictions. Key
messages for KW KW.
• DH Keep Warm Keep Well fact sheets –
particularly those translated into community
• 1 side simple prompt sheet for patients – eg
distribution through pharmacies (with scripts) /
libraries / other. ‘Top Tips’ for keeping warm in
• Media bulletins and editorial to support press
release etc etc.
What will this add
• Systematic means of delivering the Keep Warm
Keep Well message to key population groups /
those most at risk.
• Means of combining clinical advice with more
generic health promotion advice
• Means of starting to address one of the key
infrastructure issues – housing thermal efficiency
– getting people into systems (generally falling under
Local Authority Fuel Poverty) to improve energy
efficiency – and therefore contribute to significant
reduction in EWM and Admissions.
• Well documented effect of cold temperature on:
– Quality of life
– GP consultation
• Linear relationship between cold and the above effects
• However, evidence suggests that temperatures of 11oc and
5oc are key points.
• Significant incidence of Excess Winter Mortality and
• 80% cold related.
• This is useful for predicting emergency admissions. However
there is v limited capacity in the secondary care system to
• Good evidence underpinning the Keep Warm Keep Well message (flu jab,
smoking, wrap up warm, turn heating up)
• W Yorkshire agreed to trial more systematic delivery of a real time process
for delivery of this message to at risk an vulnerable groups – aim is to
prevent admissions / improve health.
• Real time ‘temperature forecasts’ will be disseminated to wide spectrum of
professional groups (within and outside NHS) agencies and the public.
• Passive dissemination to most.
• It is proposed that active dissemination to those on Community Matron
caseloads (in theory most vulnerable and at risk of admission) – though
• Wide range of materials to support.
• System will only have impact if acted upon – by both professionals and the
• Careful monitoring will attempt to establish the reach.
• Attributing any impact to the intervention will be very difficult.