Author Name: Samantha Lane; BSc (Hons) Veterinary Nursing Science
Stress and anxiety amongst cats is a cause of undesirable behaviour such as marking and inappropriate urination. It also plays a role in triggering or worsening feline idiopathic cystitis (FIC). These behaviour-related urinary problems are the main cause for owners seeking veterinary attention for their cats. Stress is also common and sometimes unavoidable in veterinary practice. Cats in particular become stressed in these settings due to a change in their routine, and the presence of other, unknown cats in the ward.
Feliway is a synthetic portion of a feline facial pheromone and is used to reduce anxiety and stress in cats. Feline facial pheromones are naturally secreted when cats rub or bunt their faces on their surroundings, making this an area recognised as “safe.” Due to its calming effect, it has been suggested that Feliway may be appropriate to use in the treatment of cats with behaviour-related urinary issues such as spraying and FIC, and studies have also investigated its use in the veterinary setting to determine Feliway’s efficacy at calming cats in veterinary practice.
Seven studies in total, with varying methodologies and conclusions, have investigated the efficacy of Feliway in both domestic and veterinary settings. These were all completed prior to 2007, meaning there is a clear need for research to be brought up-to-date if veterinary professionals are to continue to be reliant on Feliway in the veterinary ward and recommend its use as a treatment for behaviour-related urinary issues seen amongst cats.
Stress is a common cause of behavioural problems and some common diseases amongst cats (International Cat Care, 2013a). Potential stressors include multiple cats in the environment and abrupt changes in routine which are encountered in both domestic and veterinary settings (Gunn-Moore, 2014). Stress reduction is important for general health and minimising the spread of infectious diseases, especially in areas of high population density such as shelters and veterinary wards (Möstl et al., 2013). Anxiety is most commonly associated with urine spraying but also plays a role in inappropriate urination, such as when a cat is too nervous to use its litter tray (Herron, 2010).
Feline lower urinary tract disease (FLUTD) encompasses a number of conditions (International Cat Care 2013b). Idiopathic FLUTD, also known as feline idiopathic cystitis (FIC) is the most common of these conditions, causing 50-75% of FLUTD cases (Caney, 2011). Inappropriate urination amongst cats is the most regularly reported behavioural issue (Neilson, 2004). Accurate diagnosis leads to ideal treatment strategy and is important because up to 30% of cats presenting with urine spraying may have underlying conditions such as FLUTD (International Cat Care, 2013b; Caney, 2011; Neilson, 2004). If medical treatment is inappropriate the alternative is to address the behavioural issues that can lead to inappropriate urination (Neilson, 2004). Stress is known to trigger FIC and Feliway (CEVA Animal Health), a synthetic portion of the feline facial pheromone, has been developed to decrease anxiety-related behaviour including urine spraying and potentially symptoms of FIC (Caney, 2011; Hostutler, Chew & DiBartola, 2005).
2.0 Efficacy of Feliway
Feliway is a synthetic equivalent of a feline facial pheromone which is normally secreted when cats bunt or rub their faces on objects (Hewson, 2014; Herron, 2010). Feliway has been studied in a number of situations, including cats with urinary issues and in the veterinary environment, and although old these studies are important as no research into the efficacy of Feliway has been done since (Clark, Donovan & Shoettker, 2006).
2.1 Efficacy of Feliway on Behaviour-related Urinary Issues
Feline inappropriate urination is urination outside of an owner-designated location and is the most common behavioural issue for which cat owners seek veterinary attention (Mills, Redgate & Landsberg, 2011; Herron, 2010; Neilson, 2004). It includes house-soiling and spraying behaviour (Herron, 2010; Neilson, 2004). Anxiety is commonly associated with spraying, however it has a role in inappropriate urination, for example when a cat is too nervous to use its litter tray (Herron, 2010). Feline idiopathic cystitis (FIC), otherwise known as feline lower urinary tract disease (FLUTD), can also be triggered or worsened by anxiety and stress (Caney, 2011; Gunn-Moore & Cameron, 2004). FIC can also have a role in inappropriate urination (Caney, 2011).
Diagnosis of the cause should be carried out prior to treatment commencing; once medical causes have been ruled out, behavioural treatment can begin (Herron, 2010; Nielson, 2004). Studies investigating the efficacy of Feliway in cats with behaviour-related urine conditions include those by Frank, Erb and Houpt (1999), Hunthausen (2000), Mills and Mills (2001) Ogata and Takeuchi (2001) and Gunn-Moore and Cameron (2004). Many of these used one group of cats with observations of behaviour made before and after treatment with Feliway (Ogata & Takeuchi, 2001; Hunthausen, 2000; Frank, Erb & Houpt, 1999). Others used separate groups for controls using placebos (Gunn-Moore & Cameron, 2004; Mills and Mills, 2001). The investigators of pre- and post-treatment studies were not blinded, increasing the risk of bias due to pre-conceived ideas (Mills, Redgate and Landsberg, 2011). Sample sizes of these studies ranged between 20 and 55, however the number of participants in the study by Hunthausen (2000) is unclear. The sample size should be stated in a clinical trial to prove the results are relevant to the whole population (Sathian et al., 2010). Conversely Mills and Mills (2001) conducted a double-blinded placebo-controlled trial with adequate randomisation of 25 cats (Frank, Beauchamp & Palestrini, 2010). The investigators remained blinded to the groups until after statistical analysis. This is a strong research design which provided high-quality results as it does not allow for investigator bias (Mills, Redgate and Landsberg, 2011).
The studies that used owners for the application of Feliway in the domestic setting relied on compliance (Mills & Mills, 2001; Ogata & Takeuchi, 2001; Frank, Erb & Houpt, 1999). Non-compliance is a type of bias and could provide unreliable data (Misra, 2012). Additionally the data relies on perception which varies between owners. Mills and Mills (2001) and Frank, Erb and Houpt (1999) monitored compliance through telephone calls, and demonstrated the use of the product to the owners, allowing for continuity to increase reliability of the results. However, in both trials there was the risk of bias, as owners could have been expecting a positive result once Feliway had been applied; this negatively affects the quality of the evidence (Mills, Redgate and Landsberg, 2011).
Findings of the studies were variable. Studies that provided evidence supporting the efficacy of Feliway include Frank, Erb and Houpt (1999), Hunthausen (2000) although this had a poor design and so results may not be entirely reliable, Ogata and Takeuchi (2001) and Gunn-Moore and Cameron (2004). On the other hand, Mills and Mills (2001) provided evidence that Feliway may not be as effective in cats as expected.
Frank, Erb and Houpt (1999) provided evidence that Feliway decreases the frequency of urine spraying through significant differences. The investigators highlighted the need for a future double-blinded study despite obtaining significant results to confirm the efficacy of Feliway to minimise bias and produce more reliable results; it is for this reason that double-blinded placebo-controlled trials are considered the “gold standard” of research designs (Misra, 2012). In contrast, Gunn-Moore and Cameron (2004) showed no statistical differences, rather a trend between exposure to Feliway and duration of FIC.
Three cats were withdrawn from the study by Mills and Mills (2001), meaning the sample size was reduced to 19; although this is a small sample, the design and methods were strong due to the double-blinded placebo-controlled methodology (Misra, 2012). The study showed a significant difference (P=0.004) in the mean level of spraying before and after Feliway application. There was a decrease in the mean number of sprays in the placebo group but no significant differences. Four cats were found to improve whilst using the placebo; this could be due to bias or the placebo effect when the owner experienced their expected effect of the use of Feliway (American Cancer Society, 2014). Because of this the researchers concluded that the efficacy of a treatment cannot be determined by reduction in spraying alone. The study also proved that there was a significant relationship between the amount of spraying and the duration of Feliway use, meaning that it is not an instantaneous treatment, rather the effects cumulate over time. The conclusions drawn from the study were fair, and the need for further research was highlighted.
Similar to that by Mills and Mills (2001) a study by Gunn-Moore and Cameron (2004) used a placebo in a randomised, double-blinded, placebo-controlled, crossover trial which appeared to be a strong design, to investigate the use of Feliway in the treatment of FIC (Gunn-Moore & Cameron, 2004). Similar to the majority of other studies investigating Feliway, the study had strict inclusion criteria. Studies that did not have adequate inclusion criteria were those by Hunthausen (2000) and Griffith, Steigerwald and Buffington (2000), a study into Feliway in the veterinary ward.
The study by Gunn-Moore and Cameron (2004) included just 12 cats, which suggests the results may not apply to the whole feline population. The cats were however randomly assigned groups which strengthens the study. Owners carried out the trial in the domestic setting; this could leave the results open to bias and lack of compliance could affect the comparability of the results, leading to further bias (Armijo-olivo, Warren & Magee, 2009). Data collection involved using analogue scales and the use of diaries, which could have been influenced by bias or perception.
Of the 12 cats enrolled onto the study, just seven produced usable data because three cats were unable to complete the trial and two owners lost their data. As the initial sample was small this further reduces reliability of the results as there is a possibility the results may not apply to the population. The mean and standard deviation showed a trend in favour of the use of Feliway in management of FIC, however there were no significant differences to prove this. Four owners noticed no difference between the Feliway and placebo, indicating the possibility of a placebo effect amongst owners, however as the sample was small this could have just been inefficacy of the Feliway. Placebo-controlled trials can only determine statistical difference, and although this is useful the results may be clinically insignificant (Rajagopal, 2006). Despite the results indicating a trend between the use of Feliway and improvement of FIC, the lack of significant differences between treatment groups does not provide concrete evidence to support the efficacy of Feliway in FIC management. Therefore further research should be undertaken to investigate this.
2.2 Efficacy of Feliway in Hospitalised Cats
Two primary papers have been published concerning hospitalised cats, however neither provide strong evidence that Feliway is effective in this situation (Kronen et al., 2006; Griffith, Steigerwald & Buffington, 2000).
In a block-randomised, blinded study investigating the use of Feliway to calm cats prior to intravenous catheterisation, 77 cats were allocated to one of four treatment groups by lottery (Kronen et al., 2006). Randomised allocation enhances study design because it allows for a good representation of the population in each group (Fives et al., 2013). All cats received a generic premedication and the cats in two of the treatment groups, “aceFFP” and “acePlac,” also received acepromazine. All drugs can affect individuals differently and this was taken into account in the analysis of results (Hussar, 2013).
The study by Griffith, Steigerwald and Buffington (2000) included two double-blinded studies, a design that is usually considered strong as it reduces investigator influences on the result due to misconceptions or prejudices (Neppe, 2008). However the methodology was flawed; systematic allocation for treatment group was used instead of randomised, meaning the differences demonstrated in the results cannot be ultimately attributed to the treatments (Norman & Streiner, 2003). Random allocation of participants to treatment groups can increase internal validity, minimising systematic error (bias) (Fives et al., 2013). In the second study half the cats had a cat carrier placed into the cage and the investigators used no placebo or control, meaning there was no baseline for comparison between the groups (American Cancer Society, 2014).
The study by Kronen et al. (2006) had a complex design with appropriate blinding, randomisation and controls in place. Despite the strong design there was insufficient evidence that Feliway was effective at calming cats that were not administered acepromazine because exposure to Feliway did not significantly reduce struggling in these cats. The results of the study showed variability in the opinions of assessors, affecting reliability. There were no measures in place to decrease inter-observer variability except markings on the cage floor to allow for easier determination of the cats’ positions in their cages. The complex methodology leads to results which were difficult to interpret due to multiple variables being measured and compared. The assessment tool used for the cats’ behaviour was modified from a previous study, which may or may not have been validated. The investigators concluded that Feliway has an additional calming effect in cats administered acepromazine and a lesser effect in those without, however there are no significant differences within data sets to prove this. Griffith, Steigerwald and Buffington (2000) concluded that Feliway can increase food intake in hospitalised cats, however the cats with the carrier showed more interest in food. A study by Vinke, Godijn and Van der Leij (2014) showed that the provision of a hiding place for shelter cats significantly lowered stress (P<0.001), therefore the carrier in the study by Griffith, Steigerwald and Buffington (2000) may have influenced the validity of the results of the efficacy of Feliway.
There are few studies investigating the efficacy of Feliway in any setting, and the trials that have been completed produced variable results. There are a range of research designs, including double-blinded, placebo controlled trials and pre- and post-treatment investigations. There are advantages and disadvantages to both, however blinded trials including control groups are usually preferred as there is less risk of bias as influences due to misconceptions and prejudices are eliminated. Although outdated research is often invalid due to changing theories, these studies are important as so little research has been completed since their publishing. Based on the studies analysed the efficacy of Feliway on reducing stress is unclear. It has been shown to play a role in reducing stress in cats but there is a requirement for further investigation to examine the effects of Feliway in both behaviour-related urinary problems and stress in the veterinary practice. As the majority of studies focusing on pheromonatherapy are old, there is a need for more recent data to increase validity and bring research up-to-date if veterinarians are to continue using Feliway as a sole treatment for urine spraying and FIC. As all cats are individual it is important to consider other methods of stress reduction, for example the addition of hiding places in veterinary kennels or dealing with stressors in the home appropriately before relying on Feliway as a management strategy.
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